Abstract

We report on the measurement of somatosensory-evoked and spontaneous magnetoencephalography (MEG) signals with a chip-scale atomic magnetometer (CSAM) based on optical spectroscopy of alkali atoms. The uncooled, fiber-coupled CSAM has a sensitive volume of 0.77 mm3 inside a sensor head of volume 1 cm3 and enabled convenient handling, similar to an electroencephalography (EEG) electrode. When positioned over O1 of a healthy human subject, α-oscillations were observed in the component of the magnetic field perpendicular to the scalp surface. Furthermore, by stimulation at the right wrist of the subject, somatosensory-evoked fields were measured with the sensors placed over C3. Higher noise levels of the CSAM were partly compensated by higher signal amplitudes due to the shorter distance between CSAM and scalp.

© 2012 OSA

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2010

H. B. Dang, A. C. Maloof, and M. V. Romalis, “Ultrahigh sensitivity magnetic field and magnetization measurements with an atomic magnetometer,” Appl. Phys. Lett.97(15), 151110 (2010).
[CrossRef]

S. Taue, Y. Sugihara, T. Kobayashi, S. Ichihara, K. Ishikawa, and N. Mizutani, “Development of a highly sensitive optically pumped atomic magnetometer for biomagnetic field measurements: A phantom study,” IEEE Trans. Magn.46(9), 3635–3638 (2010).
[CrossRef]

C. Johnson, P. D. D. Schwindt, and M. Weisend, “Magnetoencephalography with a two-color pump-probe, fiber-coupled atomic magnetometer,” Appl. Phys. Lett.97(24), 243703 (2010).
[CrossRef]

W. C. Griffith, S. Knappe, and J. Kitching, “Femtotesla atomic magnetometry in a microfabricated vapor cell,” Opt. Express18(26), 27167–27172 (2010).
[CrossRef] [PubMed]

S. Knappe, T. H. Sander, O. Kosch, F. Wiekhorst, J. Kitching, and L. Trahms, “Cross-validation of microfabricated atomic magnetometers with superconducting quantum interference devices for biomagnetic applications,” Appl. Phys. Lett.97(13), 133703 (2010).
[CrossRef]

2009

G. Bison, N. Castagna, A. Hofer, P. Knowles, J. L. Schenker, M. Kasprzak, H. Saudan, and A. Weis, “A room temperature 19-channel magnetic field mapping device for cardiac signals,” Appl. Phys. Lett.95(17), 173701 (2009).
[CrossRef]

I. M. Savukov, V. S. Zotev, P. L. Volegov, M. A. Espy, A. N. Matlashov, J. J. Gomez, and R. H. Kraus, “MRI with an atomic magnetometer suitable for practical imaging applications,” J. Magn. Reson.199(2), 188–191 (2009).
[CrossRef] [PubMed]

S. M. Stufflebeam, N. Tanaka, and S. P. Ahlfors, “Clinical applications of magnetoencephalography,” Hum. Brain Mapp.30(6), 1813–1823 (2009).
[CrossRef] [PubMed]

2007

V. Shah, S. Knappe, P. D. D. Schwindt, and J. Kitching, “Subpicotesla atomic magnetometry with a microfabricated vapour cell,” Nat. Photonics1(11), 649–652 (2007).
[CrossRef]

2006

H. Xia, A. Ben-Amar Baranga, D. Hoffman, and M. V. Romalis, “Magnetoencephalography with an atomic magnetometer,” Appl. Phys. Lett.89(21), 211104 (2006).
[CrossRef]

S. Xu, V. V. Yashchuk, M. H. Donaldson, S. M. Rochester, D. Budker, and A. Pines, “Magnetic resonance imaging with an optical atomic magnetometer,” Proc. Natl. Acad. Sci. U.S.A.103(34), 12668–12671 (2006).
[CrossRef] [PubMed]

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

2005

T. H. Sander, M. Burghoff, G. Curio, and L. Trahms, “Single evoked somatosensory MEG responses extracted by time delayed decorrelation,” IEEE Trans. Signal Process.53(9), 3384–3392 (2005).
[CrossRef]

S. Taulu and M. Kajola, “Presentation of electromagnetic multichannel data: the signal space separation method,” J. Appl. Phys.97(12), 124905 (2005).
[CrossRef]

S. Knappe, V. Gerginov, P. D. D. Schwindt, V. Shah, H. G. Robinson, L. Hollberg, and J. Kitching, “Atomic vapor cells for chip-scale atomic clocks with improved long-term frequency stability,” Opt. Lett.30(18), 2351–2353 (2005).
[CrossRef] [PubMed]

2004

M. Burghoff, T. H. Sander, A. Schnabel, D. Drung, L. Trahms, G. Curio, and B.-M. Mackert, “DC Magnetoencephalography: Direct measurement in a magnetically extremely-well shielded room,” Appl. Phys. Lett.85(25), 6278–6280 (2004).
[CrossRef]

2003

G. Bison, R. Wynands, and A. Weis, “Dynamical mapping of the human cardiomagnetic field with a room-temperature, laser-optical sensor,” Opt. Express11(8), 904–909 (2003).
[CrossRef] [PubMed]

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

2002

J. C. Allred, R. N. Lyman, T. W. Kornack, and M. V. Romalis, “High-sensitivity atomic magnetometer unaffected by spin-exchange relaxation,” Phys. Rev. Lett.89(13), 130801 (2002).
[CrossRef] [PubMed]

1999

R. Hari and N. Forss, “Magnetoencephalography in the study of human somatosensory cortical processing,” Philos. Trans. R. Soc. Lond. B Biol. Sci.354(1387), 1145–1154 (1999).
[CrossRef] [PubMed]

1993

A. I. Ahonen, M. S. Hämäläinen, R. J. Ilmoniemi, M. J. Kajola, J. E. T. Knuutila, J. T. Simola, and V. A. Vilkman, “Sampling theory for neuromagnetic detector arrays,” IEEE Trans. Biomed. Eng.40(9), 859–869 (1993).
[CrossRef] [PubMed]

M. Hämäläinen, R. Hari, R. J. Ilmoniemi, J. Knuutila, and O. V. Lounasmaa, “Magnetoencephalography – theory, instrumentation, and applications to noninvasive studies of the working human brain,” Rev. Mod. Phys.65(2), 413–497 (1993).
[CrossRef]

1989

J. Tiihonen, R. Hari, and M. Hämäläinen, “Early deflections of cerebral magnetic responses to median nerve stimulation,” Electroencephalogr. Clin. Neurophysiol.74(4), 290–296 (1989).
[CrossRef] [PubMed]

1978

M. N. Livanov, A. N. Kozlov, A. V. Korinevskiĭ, V. P. Markin, and S. E. Sinel’nikova, “O registratsii magnitnykh poleĭ cheloveka [Recording of human magnetic fields],” Dokl. Akad. Nauk SSSR238(1), 253–256 (1978).
[PubMed]

1969

J. Dupont-Roc, S. Haroche, and C. Cohen-Tannoudji, “Detection of very weak magnetic fields (10−9 gauss) by 87Rb zero-field level crossing resonances,” Phys. Lett. A28(9), 638–639 (1969).
[CrossRef]

1968

D. Cohen, “Magnetoencephalography: evidence of magnetic fields produced by alpha-rhythm currents,” Science161(3843), 784–786 (1968).
[CrossRef] [PubMed]

Ahlfors, S. P.

S. M. Stufflebeam, N. Tanaka, and S. P. Ahlfors, “Clinical applications of magnetoencephalography,” Hum. Brain Mapp.30(6), 1813–1823 (2009).
[CrossRef] [PubMed]

Ahonen, A. I.

A. I. Ahonen, M. S. Hämäläinen, R. J. Ilmoniemi, M. J. Kajola, J. E. T. Knuutila, J. T. Simola, and V. A. Vilkman, “Sampling theory for neuromagnetic detector arrays,” IEEE Trans. Biomed. Eng.40(9), 859–869 (1993).
[CrossRef] [PubMed]

Allred, J. C.

J. C. Allred, R. N. Lyman, T. W. Kornack, and M. V. Romalis, “High-sensitivity atomic magnetometer unaffected by spin-exchange relaxation,” Phys. Rev. Lett.89(13), 130801 (2002).
[CrossRef] [PubMed]

Aronen, H. J.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Avikainen, S.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Ben-Amar Baranga, A.

H. Xia, A. Ben-Amar Baranga, D. Hoffman, and M. V. Romalis, “Magnetoencephalography with an atomic magnetometer,” Appl. Phys. Lett.89(21), 211104 (2006).
[CrossRef]

Bison, G.

G. Bison, N. Castagna, A. Hofer, P. Knowles, J. L. Schenker, M. Kasprzak, H. Saudan, and A. Weis, “A room temperature 19-channel magnetic field mapping device for cardiac signals,” Appl. Phys. Lett.95(17), 173701 (2009).
[CrossRef]

G. Bison, R. Wynands, and A. Weis, “Dynamical mapping of the human cardiomagnetic field with a room-temperature, laser-optical sensor,” Opt. Express11(8), 904–909 (2003).
[CrossRef] [PubMed]

Brander, A.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Buchfelder, M.

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

Budker, D.

S. Xu, V. V. Yashchuk, M. H. Donaldson, S. M. Rochester, D. Budker, and A. Pines, “Magnetic resonance imaging with an optical atomic magnetometer,” Proc. Natl. Acad. Sci. U.S.A.103(34), 12668–12671 (2006).
[CrossRef] [PubMed]

Burghoff, M.

T. H. Sander, M. Burghoff, G. Curio, and L. Trahms, “Single evoked somatosensory MEG responses extracted by time delayed decorrelation,” IEEE Trans. Signal Process.53(9), 3384–3392 (2005).
[CrossRef]

M. Burghoff, T. H. Sander, A. Schnabel, D. Drung, L. Trahms, G. Curio, and B.-M. Mackert, “DC Magnetoencephalography: Direct measurement in a magnetically extremely-well shielded room,” Appl. Phys. Lett.85(25), 6278–6280 (2004).
[CrossRef]

Castagna, N.

G. Bison, N. Castagna, A. Hofer, P. Knowles, J. L. Schenker, M. Kasprzak, H. Saudan, and A. Weis, “A room temperature 19-channel magnetic field mapping device for cardiac signals,” Appl. Phys. Lett.95(17), 173701 (2009).
[CrossRef]

Cohen, D.

D. Cohen, “Magnetoencephalography: evidence of magnetic fields produced by alpha-rhythm currents,” Science161(3843), 784–786 (1968).
[CrossRef] [PubMed]

Cohen-Tannoudji, C.

J. Dupont-Roc, S. Haroche, and C. Cohen-Tannoudji, “Detection of very weak magnetic fields (10−9 gauss) by 87Rb zero-field level crossing resonances,” Phys. Lett. A28(9), 638–639 (1969).
[CrossRef]

Curio, G.

T. H. Sander, M. Burghoff, G. Curio, and L. Trahms, “Single evoked somatosensory MEG responses extracted by time delayed decorrelation,” IEEE Trans. Signal Process.53(9), 3384–3392 (2005).
[CrossRef]

M. Burghoff, T. H. Sander, A. Schnabel, D. Drung, L. Trahms, G. Curio, and B.-M. Mackert, “DC Magnetoencephalography: Direct measurement in a magnetically extremely-well shielded room,” Appl. Phys. Lett.85(25), 6278–6280 (2004).
[CrossRef]

Dang, H. B.

H. B. Dang, A. C. Maloof, and M. V. Romalis, “Ultrahigh sensitivity magnetic field and magnetization measurements with an atomic magnetometer,” Appl. Phys. Lett.97(15), 151110 (2010).
[CrossRef]

Donaldson, M. H.

S. Xu, V. V. Yashchuk, M. H. Donaldson, S. M. Rochester, D. Budker, and A. Pines, “Magnetic resonance imaging with an optical atomic magnetometer,” Proc. Natl. Acad. Sci. U.S.A.103(34), 12668–12671 (2006).
[CrossRef] [PubMed]

Drung, D.

M. Burghoff, T. H. Sander, A. Schnabel, D. Drung, L. Trahms, G. Curio, and B.-M. Mackert, “DC Magnetoencephalography: Direct measurement in a magnetically extremely-well shielded room,” Appl. Phys. Lett.85(25), 6278–6280 (2004).
[CrossRef]

Druschky, K.

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

Dupont-Roc, J.

J. Dupont-Roc, S. Haroche, and C. Cohen-Tannoudji, “Detection of very weak magnetic fields (10−9 gauss) by 87Rb zero-field level crossing resonances,” Phys. Lett. A28(9), 638–639 (1969).
[CrossRef]

Espy, M. A.

I. M. Savukov, V. S. Zotev, P. L. Volegov, M. A. Espy, A. N. Matlashov, J. J. Gomez, and R. H. Kraus, “MRI with an atomic magnetometer suitable for practical imaging applications,” J. Magn. Reson.199(2), 188–191 (2009).
[CrossRef] [PubMed]

Forss, N.

R. Hari and N. Forss, “Magnetoencephalography in the study of human somatosensory cortical processing,” Philos. Trans. R. Soc. Lond. B Biol. Sci.354(1387), 1145–1154 (1999).
[CrossRef] [PubMed]

Genow, A.

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

Gerginov, V.

Gomez, J. J.

I. M. Savukov, V. S. Zotev, P. L. Volegov, M. A. Espy, A. N. Matlashov, J. J. Gomez, and R. H. Kraus, “MRI with an atomic magnetometer suitable for practical imaging applications,” J. Magn. Reson.199(2), 188–191 (2009).
[CrossRef] [PubMed]

Griffith, W. C.

Hämäläinen, M.

M. Hämäläinen, R. Hari, R. J. Ilmoniemi, J. Knuutila, and O. V. Lounasmaa, “Magnetoencephalography – theory, instrumentation, and applications to noninvasive studies of the working human brain,” Rev. Mod. Phys.65(2), 413–497 (1993).
[CrossRef]

J. Tiihonen, R. Hari, and M. Hämäläinen, “Early deflections of cerebral magnetic responses to median nerve stimulation,” Electroencephalogr. Clin. Neurophysiol.74(4), 290–296 (1989).
[CrossRef] [PubMed]

Hämäläinen, M. S.

A. I. Ahonen, M. S. Hämäläinen, R. J. Ilmoniemi, M. J. Kajola, J. E. T. Knuutila, J. T. Simola, and V. A. Vilkman, “Sampling theory for neuromagnetic detector arrays,” IEEE Trans. Biomed. Eng.40(9), 859–869 (1993).
[CrossRef] [PubMed]

Hari, R.

R. Hari and N. Forss, “Magnetoencephalography in the study of human somatosensory cortical processing,” Philos. Trans. R. Soc. Lond. B Biol. Sci.354(1387), 1145–1154 (1999).
[CrossRef] [PubMed]

M. Hämäläinen, R. Hari, R. J. Ilmoniemi, J. Knuutila, and O. V. Lounasmaa, “Magnetoencephalography – theory, instrumentation, and applications to noninvasive studies of the working human brain,” Rev. Mod. Phys.65(2), 413–497 (1993).
[CrossRef]

J. Tiihonen, R. Hari, and M. Hämäläinen, “Early deflections of cerebral magnetic responses to median nerve stimulation,” Electroencephalogr. Clin. Neurophysiol.74(4), 290–296 (1989).
[CrossRef] [PubMed]

Haroche, S.

J. Dupont-Roc, S. Haroche, and C. Cohen-Tannoudji, “Detection of very weak magnetic fields (10−9 gauss) by 87Rb zero-field level crossing resonances,” Phys. Lett. A28(9), 638–639 (1969).
[CrossRef]

Hofer, A.

G. Bison, N. Castagna, A. Hofer, P. Knowles, J. L. Schenker, M. Kasprzak, H. Saudan, and A. Weis, “A room temperature 19-channel magnetic field mapping device for cardiac signals,” Appl. Phys. Lett.95(17), 173701 (2009).
[CrossRef]

Hoffman, D.

H. Xia, A. Ben-Amar Baranga, D. Hoffman, and M. V. Romalis, “Magnetoencephalography with an atomic magnetometer,” Appl. Phys. Lett.89(21), 211104 (2006).
[CrossRef]

Hollberg, L.

Hopfengärtner, R.

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

Hummel, C.

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

Huttunen, J.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Ichihara, S.

S. Taue, Y. Sugihara, T. Kobayashi, S. Ichihara, K. Ishikawa, and N. Mizutani, “Development of a highly sensitive optically pumped atomic magnetometer for biomagnetic field measurements: A phantom study,” IEEE Trans. Magn.46(9), 3635–3638 (2010).
[CrossRef]

Ilmoniemi, R. J.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

A. I. Ahonen, M. S. Hämäläinen, R. J. Ilmoniemi, M. J. Kajola, J. E. T. Knuutila, J. T. Simola, and V. A. Vilkman, “Sampling theory for neuromagnetic detector arrays,” IEEE Trans. Biomed. Eng.40(9), 859–869 (1993).
[CrossRef] [PubMed]

M. Hämäläinen, R. Hari, R. J. Ilmoniemi, J. Knuutila, and O. V. Lounasmaa, “Magnetoencephalography – theory, instrumentation, and applications to noninvasive studies of the working human brain,” Rev. Mod. Phys.65(2), 413–497 (1993).
[CrossRef]

Ishikawa, K.

S. Taue, Y. Sugihara, T. Kobayashi, S. Ichihara, K. Ishikawa, and N. Mizutani, “Development of a highly sensitive optically pumped atomic magnetometer for biomagnetic field measurements: A phantom study,” IEEE Trans. Magn.46(9), 3635–3638 (2010).
[CrossRef]

Jääskeläinen, J. E.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Johnson, C.

C. Johnson, P. D. D. Schwindt, and M. Weisend, “Magnetoencephalography with a two-color pump-probe, fiber-coupled atomic magnetometer,” Appl. Phys. Lett.97(24), 243703 (2010).
[CrossRef]

Kajola, M.

S. Taulu and M. Kajola, “Presentation of electromagnetic multichannel data: the signal space separation method,” J. Appl. Phys.97(12), 124905 (2005).
[CrossRef]

Kajola, M. J.

A. I. Ahonen, M. S. Hämäläinen, R. J. Ilmoniemi, M. J. Kajola, J. E. T. Knuutila, J. T. Simola, and V. A. Vilkman, “Sampling theory for neuromagnetic detector arrays,” IEEE Trans. Biomed. Eng.40(9), 859–869 (1993).
[CrossRef] [PubMed]

Kaltenhäuser, M.

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

Kasprzak, M.

G. Bison, N. Castagna, A. Hofer, P. Knowles, J. L. Schenker, M. Kasprzak, H. Saudan, and A. Weis, “A room temperature 19-channel magnetic field mapping device for cardiac signals,” Appl. Phys. Lett.95(17), 173701 (2009).
[CrossRef]

Kirveskari, E.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Kitching, J.

W. C. Griffith, S. Knappe, and J. Kitching, “Femtotesla atomic magnetometry in a microfabricated vapor cell,” Opt. Express18(26), 27167–27172 (2010).
[CrossRef] [PubMed]

S. Knappe, T. H. Sander, O. Kosch, F. Wiekhorst, J. Kitching, and L. Trahms, “Cross-validation of microfabricated atomic magnetometers with superconducting quantum interference devices for biomagnetic applications,” Appl. Phys. Lett.97(13), 133703 (2010).
[CrossRef]

V. Shah, S. Knappe, P. D. D. Schwindt, and J. Kitching, “Subpicotesla atomic magnetometry with a microfabricated vapour cell,” Nat. Photonics1(11), 649–652 (2007).
[CrossRef]

S. Knappe, V. Gerginov, P. D. D. Schwindt, V. Shah, H. G. Robinson, L. Hollberg, and J. Kitching, “Atomic vapor cells for chip-scale atomic clocks with improved long-term frequency stability,” Opt. Lett.30(18), 2351–2353 (2005).
[CrossRef] [PubMed]

Knappe, S.

S. Knappe, T. H. Sander, O. Kosch, F. Wiekhorst, J. Kitching, and L. Trahms, “Cross-validation of microfabricated atomic magnetometers with superconducting quantum interference devices for biomagnetic applications,” Appl. Phys. Lett.97(13), 133703 (2010).
[CrossRef]

W. C. Griffith, S. Knappe, and J. Kitching, “Femtotesla atomic magnetometry in a microfabricated vapor cell,” Opt. Express18(26), 27167–27172 (2010).
[CrossRef] [PubMed]

V. Shah, S. Knappe, P. D. D. Schwindt, and J. Kitching, “Subpicotesla atomic magnetometry with a microfabricated vapour cell,” Nat. Photonics1(11), 649–652 (2007).
[CrossRef]

S. Knappe, V. Gerginov, P. D. D. Schwindt, V. Shah, H. G. Robinson, L. Hollberg, and J. Kitching, “Atomic vapor cells for chip-scale atomic clocks with improved long-term frequency stability,” Opt. Lett.30(18), 2351–2353 (2005).
[CrossRef] [PubMed]

Knowles, P.

G. Bison, N. Castagna, A. Hofer, P. Knowles, J. L. Schenker, M. Kasprzak, H. Saudan, and A. Weis, “A room temperature 19-channel magnetic field mapping device for cardiac signals,” Appl. Phys. Lett.95(17), 173701 (2009).
[CrossRef]

Knuutila, J.

M. Hämäläinen, R. Hari, R. J. Ilmoniemi, J. Knuutila, and O. V. Lounasmaa, “Magnetoencephalography – theory, instrumentation, and applications to noninvasive studies of the working human brain,” Rev. Mod. Phys.65(2), 413–497 (1993).
[CrossRef]

Knuutila, J. E. T.

A. I. Ahonen, M. S. Hämäläinen, R. J. Ilmoniemi, M. J. Kajola, J. E. T. Knuutila, J. T. Simola, and V. A. Vilkman, “Sampling theory for neuromagnetic detector arrays,” IEEE Trans. Biomed. Eng.40(9), 859–869 (1993).
[CrossRef] [PubMed]

Kobayashi, T.

S. Taue, Y. Sugihara, T. Kobayashi, S. Ichihara, K. Ishikawa, and N. Mizutani, “Development of a highly sensitive optically pumped atomic magnetometer for biomagnetic field measurements: A phantom study,” IEEE Trans. Magn.46(9), 3635–3638 (2010).
[CrossRef]

Korinevskii, A. V.

M. N. Livanov, A. N. Kozlov, A. V. Korinevskiĭ, V. P. Markin, and S. E. Sinel’nikova, “O registratsii magnitnykh poleĭ cheloveka [Recording of human magnetic fields],” Dokl. Akad. Nauk SSSR238(1), 253–256 (1978).
[PubMed]

Kornack, T. W.

J. C. Allred, R. N. Lyman, T. W. Kornack, and M. V. Romalis, “High-sensitivity atomic magnetometer unaffected by spin-exchange relaxation,” Phys. Rev. Lett.89(13), 130801 (2002).
[CrossRef] [PubMed]

Korvenoja, A.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Kosch, O.

S. Knappe, T. H. Sander, O. Kosch, F. Wiekhorst, J. Kitching, and L. Trahms, “Cross-validation of microfabricated atomic magnetometers with superconducting quantum interference devices for biomagnetic applications,” Appl. Phys. Lett.97(13), 133703 (2010).
[CrossRef]

Kovala, T.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Kozlov, A. N.

M. N. Livanov, A. N. Kozlov, A. V. Korinevskiĭ, V. P. Markin, and S. E. Sinel’nikova, “O registratsii magnitnykh poleĭ cheloveka [Recording of human magnetic fields],” Dokl. Akad. Nauk SSSR238(1), 253–256 (1978).
[PubMed]

Kraus, R. H.

I. M. Savukov, V. S. Zotev, P. L. Volegov, M. A. Espy, A. N. Matlashov, J. J. Gomez, and R. H. Kraus, “MRI with an atomic magnetometer suitable for practical imaging applications,” J. Magn. Reson.199(2), 188–191 (2009).
[CrossRef] [PubMed]

Livanov, M. N.

M. N. Livanov, A. N. Kozlov, A. V. Korinevskiĭ, V. P. Markin, and S. E. Sinel’nikova, “O registratsii magnitnykh poleĭ cheloveka [Recording of human magnetic fields],” Dokl. Akad. Nauk SSSR238(1), 253–256 (1978).
[PubMed]

Lounasmaa, O. V.

M. Hämäläinen, R. Hari, R. J. Ilmoniemi, J. Knuutila, and O. V. Lounasmaa, “Magnetoencephalography – theory, instrumentation, and applications to noninvasive studies of the working human brain,” Rev. Mod. Phys.65(2), 413–497 (1993).
[CrossRef]

Lyman, R. N.

J. C. Allred, R. N. Lyman, T. W. Kornack, and M. V. Romalis, “High-sensitivity atomic magnetometer unaffected by spin-exchange relaxation,” Phys. Rev. Lett.89(13), 130801 (2002).
[CrossRef] [PubMed]

Mackert, B.-M.

M. Burghoff, T. H. Sander, A. Schnabel, D. Drung, L. Trahms, G. Curio, and B.-M. Mackert, “DC Magnetoencephalography: Direct measurement in a magnetically extremely-well shielded room,” Appl. Phys. Lett.85(25), 6278–6280 (2004).
[CrossRef]

Mäkelä, J. P.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Maloof, A. C.

H. B. Dang, A. C. Maloof, and M. V. Romalis, “Ultrahigh sensitivity magnetic field and magnetization measurements with an atomic magnetometer,” Appl. Phys. Lett.97(15), 151110 (2010).
[CrossRef]

Markin, V. P.

M. N. Livanov, A. N. Kozlov, A. V. Korinevskiĭ, V. P. Markin, and S. E. Sinel’nikova, “O registratsii magnitnykh poleĭ cheloveka [Recording of human magnetic fields],” Dokl. Akad. Nauk SSSR238(1), 253–256 (1978).
[PubMed]

Matlashov, A. N.

I. M. Savukov, V. S. Zotev, P. L. Volegov, M. A. Espy, A. N. Matlashov, J. J. Gomez, and R. H. Kraus, “MRI with an atomic magnetometer suitable for practical imaging applications,” J. Magn. Reson.199(2), 188–191 (2009).
[CrossRef] [PubMed]

Mizutani, N.

S. Taue, Y. Sugihara, T. Kobayashi, S. Ichihara, K. Ishikawa, and N. Mizutani, “Development of a highly sensitive optically pumped atomic magnetometer for biomagnetic field measurements: A phantom study,” IEEE Trans. Magn.46(9), 3635–3638 (2010).
[CrossRef]

Pines, A.

S. Xu, V. V. Yashchuk, M. H. Donaldson, S. M. Rochester, D. Budker, and A. Pines, “Magnetic resonance imaging with an optical atomic magnetometer,” Proc. Natl. Acad. Sci. U.S.A.103(34), 12668–12671 (2006).
[CrossRef] [PubMed]

Robinson, H. G.

Rochester, S. M.

S. Xu, V. V. Yashchuk, M. H. Donaldson, S. M. Rochester, D. Budker, and A. Pines, “Magnetic resonance imaging with an optical atomic magnetometer,” Proc. Natl. Acad. Sci. U.S.A.103(34), 12668–12671 (2006).
[CrossRef] [PubMed]

Romalis, M. V.

H. B. Dang, A. C. Maloof, and M. V. Romalis, “Ultrahigh sensitivity magnetic field and magnetization measurements with an atomic magnetometer,” Appl. Phys. Lett.97(15), 151110 (2010).
[CrossRef]

H. Xia, A. Ben-Amar Baranga, D. Hoffman, and M. V. Romalis, “Magnetoencephalography with an atomic magnetometer,” Appl. Phys. Lett.89(21), 211104 (2006).
[CrossRef]

J. C. Allred, R. N. Lyman, T. W. Kornack, and M. V. Romalis, “High-sensitivity atomic magnetometer unaffected by spin-exchange relaxation,” Phys. Rev. Lett.89(13), 130801 (2002).
[CrossRef] [PubMed]

Romstöck, J.

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

Salli, E.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Sander, T. H.

S. Knappe, T. H. Sander, O. Kosch, F. Wiekhorst, J. Kitching, and L. Trahms, “Cross-validation of microfabricated atomic magnetometers with superconducting quantum interference devices for biomagnetic applications,” Appl. Phys. Lett.97(13), 133703 (2010).
[CrossRef]

T. H. Sander, M. Burghoff, G. Curio, and L. Trahms, “Single evoked somatosensory MEG responses extracted by time delayed decorrelation,” IEEE Trans. Signal Process.53(9), 3384–3392 (2005).
[CrossRef]

M. Burghoff, T. H. Sander, A. Schnabel, D. Drung, L. Trahms, G. Curio, and B.-M. Mackert, “DC Magnetoencephalography: Direct measurement in a magnetically extremely-well shielded room,” Appl. Phys. Lett.85(25), 6278–6280 (2004).
[CrossRef]

Saudan, H.

G. Bison, N. Castagna, A. Hofer, P. Knowles, J. L. Schenker, M. Kasprzak, H. Saudan, and A. Weis, “A room temperature 19-channel magnetic field mapping device for cardiac signals,” Appl. Phys. Lett.95(17), 173701 (2009).
[CrossRef]

Savukov, I. M.

I. M. Savukov, V. S. Zotev, P. L. Volegov, M. A. Espy, A. N. Matlashov, J. J. Gomez, and R. H. Kraus, “MRI with an atomic magnetometer suitable for practical imaging applications,” J. Magn. Reson.199(2), 188–191 (2009).
[CrossRef] [PubMed]

Scheler, G.

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

Schenker, J. L.

G. Bison, N. Castagna, A. Hofer, P. Knowles, J. L. Schenker, M. Kasprzak, H. Saudan, and A. Weis, “A room temperature 19-channel magnetic field mapping device for cardiac signals,” Appl. Phys. Lett.95(17), 173701 (2009).
[CrossRef]

Schnabel, A.

M. Burghoff, T. H. Sander, A. Schnabel, D. Drung, L. Trahms, G. Curio, and B.-M. Mackert, “DC Magnetoencephalography: Direct measurement in a magnetically extremely-well shielded room,” Appl. Phys. Lett.85(25), 6278–6280 (2004).
[CrossRef]

Schwindt, P. D. D.

C. Johnson, P. D. D. Schwindt, and M. Weisend, “Magnetoencephalography with a two-color pump-probe, fiber-coupled atomic magnetometer,” Appl. Phys. Lett.97(24), 243703 (2010).
[CrossRef]

V. Shah, S. Knappe, P. D. D. Schwindt, and J. Kitching, “Subpicotesla atomic magnetometry with a microfabricated vapour cell,” Nat. Photonics1(11), 649–652 (2007).
[CrossRef]

S. Knappe, V. Gerginov, P. D. D. Schwindt, V. Shah, H. G. Robinson, L. Hollberg, and J. Kitching, “Atomic vapor cells for chip-scale atomic clocks with improved long-term frequency stability,” Opt. Lett.30(18), 2351–2353 (2005).
[CrossRef] [PubMed]

Seppä, M.

A. Korvenoja, E. Kirveskari, H. J. Aronen, S. Avikainen, A. Brander, J. Huttunen, R. J. Ilmoniemi, J. E. Jääskeläinen, T. Kovala, J. P. Mäkelä, E. Salli, and M. Seppä, “Sensorimotor cortex localization: comparison of magnetoencephalography, functional MR imaging, and intraoperative cortical mapping,” Radiology241(1), 213–222 (2006).
[CrossRef] [PubMed]

Shah, V.

Simola, J. T.

A. I. Ahonen, M. S. Hämäläinen, R. J. Ilmoniemi, M. J. Kajola, J. E. T. Knuutila, J. T. Simola, and V. A. Vilkman, “Sampling theory for neuromagnetic detector arrays,” IEEE Trans. Biomed. Eng.40(9), 859–869 (1993).
[CrossRef] [PubMed]

Sinel’nikova, S. E.

M. N. Livanov, A. N. Kozlov, A. V. Korinevskiĭ, V. P. Markin, and S. E. Sinel’nikova, “O registratsii magnitnykh poleĭ cheloveka [Recording of human magnetic fields],” Dokl. Akad. Nauk SSSR238(1), 253–256 (1978).
[PubMed]

Stefan, H.

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

Stufflebeam, S. M.

S. M. Stufflebeam, N. Tanaka, and S. P. Ahlfors, “Clinical applications of magnetoencephalography,” Hum. Brain Mapp.30(6), 1813–1823 (2009).
[CrossRef] [PubMed]

Sugihara, Y.

S. Taue, Y. Sugihara, T. Kobayashi, S. Ichihara, K. Ishikawa, and N. Mizutani, “Development of a highly sensitive optically pumped atomic magnetometer for biomagnetic field measurements: A phantom study,” IEEE Trans. Magn.46(9), 3635–3638 (2010).
[CrossRef]

Tanaka, N.

S. M. Stufflebeam, N. Tanaka, and S. P. Ahlfors, “Clinical applications of magnetoencephalography,” Hum. Brain Mapp.30(6), 1813–1823 (2009).
[CrossRef] [PubMed]

Taue, S.

S. Taue, Y. Sugihara, T. Kobayashi, S. Ichihara, K. Ishikawa, and N. Mizutani, “Development of a highly sensitive optically pumped atomic magnetometer for biomagnetic field measurements: A phantom study,” IEEE Trans. Magn.46(9), 3635–3638 (2010).
[CrossRef]

Taulu, S.

S. Taulu and M. Kajola, “Presentation of electromagnetic multichannel data: the signal space separation method,” J. Appl. Phys.97(12), 124905 (2005).
[CrossRef]

Tiihonen, J.

J. Tiihonen, R. Hari, and M. Hämäläinen, “Early deflections of cerebral magnetic responses to median nerve stimulation,” Electroencephalogr. Clin. Neurophysiol.74(4), 290–296 (1989).
[CrossRef] [PubMed]

Tilz, C.

H. Stefan, C. Hummel, G. Scheler, A. Genow, K. Druschky, C. Tilz, M. Kaltenhäuser, R. Hopfengärtner, M. Buchfelder, and J. Romstöck, “Magnetic brain source imaging of focal epileptic activity: a synopsis of 455 cases,” Brain126(11), 2396–2405 (2003).
[CrossRef] [PubMed]

Trahms, L.

S. Knappe, T. H. Sander, O. Kosch, F. Wiekhorst, J. Kitching, and L. Trahms, “Cross-validation of microfabricated atomic magnetometers with superconducting quantum interference devices for biomagnetic applications,” Appl. Phys. Lett.97(13), 133703 (2010).
[CrossRef]

T. H. Sander, M. Burghoff, G. Curio, and L. Trahms, “Single evoked somatosensory MEG responses extracted by time delayed decorrelation,” IEEE Trans. Signal Process.53(9), 3384–3392 (2005).
[CrossRef]

M. Burghoff, T. H. Sander, A. Schnabel, D. Drung, L. Trahms, G. Curio, and B.-M. Mackert, “DC Magnetoencephalography: Direct measurement in a magnetically extremely-well shielded room,” Appl. Phys. Lett.85(25), 6278–6280 (2004).
[CrossRef]

Vilkman, V. A.

A. I. Ahonen, M. S. Hämäläinen, R. J. Ilmoniemi, M. J. Kajola, J. E. T. Knuutila, J. T. Simola, and V. A. Vilkman, “Sampling theory for neuromagnetic detector arrays,” IEEE Trans. Biomed. Eng.40(9), 859–869 (1993).
[CrossRef] [PubMed]

Volegov, P. L.

I. M. Savukov, V. S. Zotev, P. L. Volegov, M. A. Espy, A. N. Matlashov, J. J. Gomez, and R. H. Kraus, “MRI with an atomic magnetometer suitable for practical imaging applications,” J. Magn. Reson.199(2), 188–191 (2009).
[CrossRef] [PubMed]

Weis, A.

G. Bison, N. Castagna, A. Hofer, P. Knowles, J. L. Schenker, M. Kasprzak, H. Saudan, and A. Weis, “A room temperature 19-channel magnetic field mapping device for cardiac signals,” Appl. Phys. Lett.95(17), 173701 (2009).
[CrossRef]

G. Bison, R. Wynands, and A. Weis, “Dynamical mapping of the human cardiomagnetic field with a room-temperature, laser-optical sensor,” Opt. Express11(8), 904–909 (2003).
[CrossRef] [PubMed]

Weisend, M.

C. Johnson, P. D. D. Schwindt, and M. Weisend, “Magnetoencephalography with a two-color pump-probe, fiber-coupled atomic magnetometer,” Appl. Phys. Lett.97(24), 243703 (2010).
[CrossRef]

Wiekhorst, F.

S. Knappe, T. H. Sander, O. Kosch, F. Wiekhorst, J. Kitching, and L. Trahms, “Cross-validation of microfabricated atomic magnetometers with superconducting quantum interference devices for biomagnetic applications,” Appl. Phys. Lett.97(13), 133703 (2010).
[CrossRef]

Wynands, R.

Xia, H.

H. Xia, A. Ben-Amar Baranga, D. Hoffman, and M. V. Romalis, “Magnetoencephalography with an atomic magnetometer,” Appl. Phys. Lett.89(21), 211104 (2006).
[CrossRef]

Xu, S.

S. Xu, V. V. Yashchuk, M. H. Donaldson, S. M. Rochester, D. Budker, and A. Pines, “Magnetic resonance imaging with an optical atomic magnetometer,” Proc. Natl. Acad. Sci. U.S.A.103(34), 12668–12671 (2006).
[CrossRef] [PubMed]

Yashchuk, V. V.

S. Xu, V. V. Yashchuk, M. H. Donaldson, S. M. Rochester, D. Budker, and A. Pines, “Magnetic resonance imaging with an optical atomic magnetometer,” Proc. Natl. Acad. Sci. U.S.A.103(34), 12668–12671 (2006).
[CrossRef] [PubMed]

Zotev, V. S.

I. M. Savukov, V. S. Zotev, P. L. Volegov, M. A. Espy, A. N. Matlashov, J. J. Gomez, and R. H. Kraus, “MRI with an atomic magnetometer suitable for practical imaging applications,” J. Magn. Reson.199(2), 188–191 (2009).
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Figures (6)

Fig. 1
Fig. 1

(Top) Vision of a flexible fiber-coupled magnetometer system. (Middle) Schematic of the microfabricated sensor head. (Bottom) Photograph of the microfabricated sensor head.

Fig. 2
Fig. 2

Sensitivity of the chip-scale magnetic sensor measured inside the magnetically-shielded room BMSR-2. (Inset) Bode plot for a typical CSAM determined by use of a coil driven by a signal generator. The 300 µs time constant was used in the MEG recordings to achieve an effective bandwidth of up to 150 Hz.

Fig. 3
Fig. 3

Sketch of the measurement positions on the head used to detect magnetoencephalographic signals. Spontaneous activity around 10 Hz linked to closing and opening of the eyes was measured with the sensor positioned above O1 (international 10-20 system for electrode positioning), whereas signals related to an electrical stimulation at the wrist were obtained over position C3.

Fig. 4
Fig. 4

Time-frequency analysis of the CSAM signal (left) and a SQUID signal (right) obtained during a repeated sequence of 20 s of eyes open followed by 20 s of eyes closed. The eyes-closed sections start at 20 s and 60 s, lasting for 20 s as indicated, and the increase in α–power in the 10 Hz band is immediately visible both in the CSAM and the SQUID signal. Measurement position was O1, as sketched in Fig. 3 (International 10-20 system).

Fig. 5
Fig. 5

Averaged SEF for three different subjects with the CSAM and SQUID data taken sequentially over position C3 as indicated in Fig. 3. Left side: CSAM result; Right side: SQUID result. The stimulus artifact at 0 ms is visible in the curves, as are the N20m and later responses, which can vary in timing. The field strength is much smaller in the SQUID curves due to the much larger distance between source and sensor, which is estimated to be 2.5 cm for the CSAMs and 6 cm for the SQUIDs.

Fig. 6
Fig. 6

Sketch of the geometry of brain current dipole source Q parallel to the surface of a horizontally layered conductor and the two sensors used in this study. Both sensors measure Bz, which is zero directly above Q, and therefore the sensors are assumed to be offset horizontally.

Tables (1)

Tables Icon

Table 1 Measured N20m amplitudes for CSAM and SQUID from the curves in Fig. 5

Equations (2)

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B z = μ 0 4π Q ×( r r Q ) e z | r r Q | 3 .
B z = μ 0 4π | Q || r r Q |sin(α) | r r Q | 3 ,

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