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Miniaturized magnetic-field sensor based on nitrogen-vacancy centers

Stefan Johansson*, Dennis Lönard*, Isabel Cardoso Barbosa, Jonas Gutsche, Jonas Witzenrath, and Artur Widera†

  • *Both authors contributed equally.
  • †Contact author: widera@rptu.de
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Phys. Rev. Applied 24, 054078 – Published 26 November, 2025

DOI: https://doi.org/10.1103/lbqj-d5zv

Abstract

The nitrogen-vacancy (NV) center in diamond is a prime candidate for quantum sensing technologies. Here, we present a fully integrated and mechanically robust fiber-based endoscopic sensor with a tip diameter of 1.25mm. On its tip, a direct laser-writing process is used to secure a diamond containing NV centers above the fiber’s core inside a polymer structure. Additionally, a metallic direct laser-written antenna structure next to the fiber facet allows efficient microwave manipulation of NV-center spins. The sensor achieves a shot-noise-limited magnetic-field sensitivity of 5.9nT/Hz using a 15−μm-sized microdiamond at a microwave power of 50mW and an optical power of 2.15mW. Using lock-in techniques, we measure a sensitivity of 51.8nT/Hz. Furthermore, we introduce a dual-fiber concept that enables, in combination with a direct laser-written structure, independent guiding of excitation and fluorescence light and thus reduces background autofluorescence. Moreover, controlled guiding of excitation light to the diamond while avoiding sample illumination may enable operation in light-sensitive environments such as biological tissue. While the demonstrated sensitivity is achieved using a single-fiber configuration, the dual-fiber approach provides a path toward integrating smaller diamonds, where autofluorescence would otherwise limit performance. We demonstrate the capability of vector magnetic-field measurements in the type of magnetic field used in state-of-the-art ultracold quantum gas experiments, opening a potential arena in which high resolution and high sensitivity are required.

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References (77)

  1. J. H. N. Loubser, and J. A. V. Wyk, Electron spin resonance in the study of diamond, Rep. Prog. Phys. 41, 1201 (1978).
  2. M. W. Doherty, N. B. Manson, P. Delaney, F. Jelezko, J. Wrachtrup, and L. C. Hollenberg, The nitrogen-vacancy colour centre in diamond, Phys. Rep. 528, 1 (2013).
  3. L. Rondin, J.-P. Tetienne, T. Hingant, J.-F. Roch, P. Maletinsky, and V. Jacques, Magnetometry with nitrogen-vacancy defects in diamond, Rep. Prog. Phys. 77, 056503 (2014).
  4. E. V. Levine, M. J. Turner, P. Kehayias, C. A. Hart, N. Langellier, R. Trubko, D. R. Glenn, R. R. Fu, and R. L. Walsworth, Principles and techniques of the quantum diamond microscope, Nanophotonics 8, 1945 (2019).
  5. A. Haque, and S. Sumaiya, An overview on the formation and processing of nitrogen-vacancy photonic centers in diamond by ion implantation, J. Manuf. Mater. Process. 1, 6 (2017).
  6. J. F. Barry, M. H. Steinecker, S. T. Alsid, J. Majumder, L. M. Pham, M. F. O’Keeffe, and D. A. Braje, Sensitive ac and dc magnetometry with nitrogen-vacancy-center ensembles in diamond, Phys. Rev. Appl. 22, 044069 (2024).
  7. V. M. Acosta, E. Bauch, M. P. Ledbetter, A. Waxman, L.-S. Bouchard, and D. Budker, Temperature dependence of the nitrogen-vacancy magnetic resonance in diamond, Phys. Rev. Lett. 104, 070801 (2010).
  8. S. Choe, J. Yoon, M. Lee, J. Oh, D. Lee, H. Kang, C.-H. Lee, and D. Lee, Precise temperature sensing with nanoscale thermal sensors based on diamond NV centers, Curr. Appl. Phys. 18, 1066 (2018).
  9. P. Kehayias, M. J. Turner, R. Trubko, J. M. Schloss, C. A. Hart, M. Wesson, D. R. Glenn, and R. L. Walsworth, Imaging crystal stress in diamond using ensembles of nitrogen-vacancy centers, Phys. Rev. B 100, 174103 (2019).
  10. F. Dolde, H. Fedder, M. W. Doherty, T. Nöbauer, F. Rempp, G. Balasubramanian, T. Wolf, F. Reinhard, L. C. L. Hollenberg, F. Jelezko, and J. Wrachtrup, Electric-field sensing using single diamond spins, Nat. Phys. 7, 459 (2011).
  11. E. Van Oort, and M. Glasbeek, Electric-field-induced modulation of spin echoes of N-V centers in diamond, Chem. Phys. Lett. 168, 529 (1990).
  12. P. Tamarat, T. Gaebel, J. R. Rabeau, M. Khan, A. D. Greentree, H. Wilson, L. C. L. Hollenberg, S. Prawer, P. Hemmer, F. Jelezko, and J. Wrachtrup, Stark shift control of single optical centers in diamond, Phys. Rev. Lett. 97, 083002 (2006).
  13. J.-P. Tetienne, N. Dontschuk, D. A. Broadway, A. Stacey, D. A. Simpson, and L. C. L. Hollenberg, Quantum imaging of current flow in graphene, Sci. Adv. 3, e1602429 (2017).
  14. J.-H. Storm, P. Hömmen, D. Drung, and R. Körber, An ultra-sensitive and wideband magnetometer based on a superconducting quantum interference device, Appl. Phys. Lett. 110, 072603 (2017).
  15. W. C. Griffith, S. Knappe, and J. Kitching, Femtotesla atomic magnetometry in a microfabricated vapor cell, Opt. Express 18, 27167 (2010).
  16. S. C. Scholten, A. J. Healey, I. O. Robertson, G. J. Abrahams, D. A. Broadway, and J.-P. Tetienne, Widefield quantum microscopy with nitrogen-vacancy centers in diamond: Strengths, limitations, and prospects, J. Appl. Phys. 130, 150902 (2021).
  17. Y. Hatano, J. Shin, J. Tanigawa, Y. Shigenobu, A. Nakazono, T. Sekiguchi, S. Onoda, T. Ohshima, K. Arai, T. Iwasaki, and M. Hatano, High-precision robust monitoring of charge/discharge current over a wide dynamic range for electric vehicle batteries using diamond quantum sensors, Sci. Rep. 12, 13991 (2022).
  18. D. A. Broadway, S. C. Scholten, C. Tan, N. Dontschuk, S. E. Lillie, B. C. Johnson, G. Zheng, Z. Wang, A. R. Oganov, S. Tian, C. Li, H. Lei, L. Wang, L. C. L. Hollenberg, and J. Tetienne, Imaging domain reversal in an ultrathin van der Waals ferromagnet, Adv. Mater. 32, 2003314 (2020).
  19. S. Steinert, F. Ziem, L. T. Hall, A. Zappe, M. Schweikert, N. Götz, A. Aird, G. Balasubramanian, L. Hollenberg, and J. Wrachtrup, Magnetic spin imaging under ambient conditions with sub-cellular resolution, Nat. Commun. 4, 1607 (2013).
  20. C. Degen, Microscopy with single spins, Nat. Nanotechnol. 3, 643 (2008).
  21. P. Rembold, N. Oshnik, M. M. Müller, S. Montangero, T. Calarco, and E. Neu, Introduction to quantum optimal control for quantum sensing with nitrogen-vacancy centers in diamond, AVS Quantum Sci. 2, 024701 (2020).
  22. E. O. Schäfer-Nolte, Development of a diamond-based scanning probe spin sensor operating at low temperature in ultra high vacuum, Ph.D. thesis, Universität Stuttgart, 2014.
  23. I. Fescenko, A. Jarmola, I. Savukov, P. Kehayias, J. Smits, J. Damron, N. Ristoff, N. Mosavian, and V. M. Acosta, Diamond magnetometer enhanced by ferrite flux concentrators, Phys. Rev. Res. 2, 023394 (2020).
  24. T. Wolf, P. Neumann, K. Nakamura, H. Sumiya, T. Ohshima, J. Isoya, and J. Wrachtrup, Subpicotesla diamond magnetometry, Phys. Rev. X 5, 041001 (2015).
  25. J. H. Shim, S.-J. Lee, S. Ghimire, J. I. Hwang, K.-G. Lee, K. Kim, M. J. Turner, C. A. Hart, R. L. Walsworth, and S. Oh, Multiplexed sensing of magnetic field and temperature in real time using a nitrogen-vacancy ensemble in diamond, Phys. Rev. Appl. 17, 014009 (2022).
  26. K. Kubota, Y. Hatano, Y. Kainuma, J. Shin, D. Nishitani, C. Shinei, T. Taniguchi, T. Teraji, S. Onoda, T. Ohshima, T. Iwasaki, and M. Hatano, Wide temperature operation of diamond quantum sensor for electric vehicle battery monitoring, Diam. Relat. Mater. 135, 109853 (2023).
  27. P. J. Scheidegger, S. Diesch, M. L. Palm, and C. L. Degen, Scanning nitrogen-vacancy magnetometry down to 350 mK, Appl. Phys. Lett. 120, 224001 (2022).
  28. G.-Q. Liu, X. Feng, N. Wang, Q. Li, and R.-B. Liu, Coherent quantum control of nitrogen-vacancy center spins near 1000 kelvin, Nat. Commun. 10, 1344 (2019).
  29. G. J. Abrahams, S. C. Scholten, A. J. Healey, I. O. Robertson, N. Dontschuk, S. Q. Lim, B. C. Johnson, D. A. Simpson, L. C. L. Hollenberg, and J.-P. Tetienne, An integrated widefield probe for practical diamond nitrogen-vacancy microscopy, Appl. Phys. Lett. 119, 254002 (2021).
  30. P. Appel, E. Neu, M. Ganzhorn, A. Barfuss, M. Batzer, M. Gratz, A. Tschöpe, and P. Maletinsky, Fabrication of all diamond scanning probes for nanoscale magnetometry, Rev. Sci. Instrum. 87, 063703 (2016).
  31. J. L. Webb, J. D. Clement, L. Troise, S. Ahmadi, G. J. Johansen, A. Huck, and U. L. Andersen, Nanotesla sensitivity magnetic field sensing using a compact diamond nitrogen-vacancy magnetometer, Appl. Phys. Lett. 114, 231103 (2019).
  32. D. Zheng, Z. Ma, W. Guo, L. Niu, J. Wang, X. Chai, Y. Li, Y. Sugawara, C. Yu, Y. Shi, X. Zhang, J. Tang, H. Guo, and J. Liu, A hand-held magnetometer based on an ensemble of nitrogen-vacancy centers in diamond, J. Phys. D: Appl. Phys. 53, 155004 (2020).
  33. F. M. Stürner, A. Brenneis, J. Kassel, U. Wostradowski, R. Rölver, T. Fuchs, K. Nakamura, H. Sumiya, S. Onoda, J. Isoya, and F. Jelezko, Compact integrated magnetometer based on nitrogen-vacancy centres in diamond, Diam. Relat. Mater. 93, 59 (2019).
  34. J. Pogorzelski, L. Horsthemke, J. Homrighausen, D. Stiegekötter, M. Gregor, and P. Glösekötter, Compact and fully integrated LED quantum sensor based on NV centers in diamond, Sensors 24, 743 (2024).
  35. R. L. Patel, L. Q. Zhou, A. C. Frangeskou, G. A. Stimpson, B. G. Breeze, A. Nikitin, M. W. Dale, E. C. Nichols, W. Thornley, B. L. Green, M. E. Newton, A. M. Edmonds, M. L. Markham, D. J. Twitchen, and G. W. Morley, Subnanotesla magnetometry with a fiber-coupled diamond sensor, Phys. Rev. Appl. 14, 044058 (2020).
  36. A. Kuwahata, T. Kitaizumi, K. Saichi, T. Sato, R. Igarashi, T. Ohshima, Y. Masuyama, T. Iwasaki, M. Hatano, F. Jelezko, M. Kusakabe, T. Yatsui, and M. Sekino, Magnetometer with nitrogen-vacancy center in a bulk diamond for detecting magnetic nanoparticles in biomedical applications, Sci. Rep. 10, 2483 (2020).
  37. F. M. Stürner, A. Brenneis, T. Buck, J. Kassel, R. Rölver, T. Fuchs, A. Savitsky, D. Suter, J. Grimmel, S. Hengesbach, M. Förtsch, K. Nakamura, H. Sumiya, S. Onoda, J. Isoya, and F. Jelezko, Integrated and portable magnetometer based on nitrogen-vacancy ensembles in diamond, Adv. Quantum Technol. 4, 2000111 (2021).
  38. D. Kim, M. I. Ibrahim, C. Foy, M. E. Trusheim, R. Han, and D. R. Englund, A CMOS-integrated quantum sensor based on nitrogen-vacancy centres, Nat. Electron. 2, 284 (2019).
  39. M. Zhao, Q. Lin, Q. Meng, W. Shan, L. Zhu, Y. Chen, T. Liu, L. Zhao, and Z. Jiang, All fiber vector magnetometer based on nitrogen-vacancy center, Nanomaterials 13, 949 (2023).
  40. I. V. Fedotov, L. V. Doronina-Amitonova, D. A. Sidorov-Biryukov, N. A. Safronov, S. Blakley, A. O. Levchenko, S. A. Zibrov, A. B. Fedotov, S. Y. Kilin, M. O. Scully, V. L. Velichansky, and A. M. Zheltikov, Fiber-optic magnetic-field imaging, Opt. Lett. 39, 6954 (2014).
  41. M. Zhao, Q. Lin, Q. Meng, W. Shan, L. Zhu, Y. Chen, L. Zhao, and Z. Jiang, Efficient fluorescence coupling microlens integrated fiber magnetometer probe based on nitrogen vacancy centers, Opt. Lett. 48, 4045 (2023).
  42. J. Homrighausen, F. Hoffmann, J. Pogorzelski, P. Glösekötter, and M. Gregor, Microscale fiber-integrated vector magnetometer with on-tip field biasing using N-V ensembles in diamond microcrystals, Phys. Rev. Appl. 22, 034029 (2024).
  43. M. M. Dong, Z. Z. Hu, Y. Liu, B. Yang, Y. J. Wang, and G. X. Du, A fiber based diamond RF B-field sensor and characterization of a small helical antenna, Appl. Phys. Lett. 113, 131105 (2018).
  44. A. Filipkowski, M. Mrózek, G. Stępniewski, M. Głowacki, D. Pysz, W. Gawlik, R. Buczyński, M. Klimczak, and A. Wojciechowski, Magnetically sensitive fiber probe with nitrogen-vacancy center nanodiamonds integrated in a suspended core, Opt. Express 30, 19573 (2022).
  45. Y. Chen, Q. Lin, H. Cheng, H. Huang, J. Shao, Y. Ye, G.-S. Liu, L. Chen, Y. Luo, and Z. Chen, Nanodiamond-based optical-fiber quantum probe for magnetic field and biological sensing, ACS Sens. 7, 3660 (2022).
  46. S. Dix, J. Gutsche, E. Waller, G. Von Freymann, and A. Widera, Fiber-tip endoscope for optical and microwave control, Rev. Sci. Instrum. 93, 095104 (2022).
  47. M. Bianco, A. Balena, M. Pisanello, F. Pisano, L. Sileo, B. Spagnolo, C. Montinaro, B. L. Sabatini, M. D. Vittorio, and F. Pisanello, Comparative study of autofluorescence in flat and tapered optical fibers towards application in depth-resolved fluorescence lifetime photometry in brain tissue, Biomed. Opt. Express 12, 993 (2021).
  48. J. A. Udovich, N. D. Kirkpatrick, A. Kano, A. West Rynes, U. Utzinger, and A. F. Gmitro, Spectral background and transmission characteristics of fiber optic imaging bundles, Appl. Opt. 47, 4560 (2008).
  49. Y. Li, F. A. Gerritsma, S. Kurdi, N. Codreanu, S. Gröblacher, R. Hanson, R. Norte, and T. van der Sar, A fiber-coupled scanning magnetometer with nitrogen-vacancy spins in a diamond nanobeam, ACS Photonics 10, 1671 (2023).
  50. H. Patrick, S. L. Gilbert, and A. Lidgard, Decrease of fluorescence in optical fiber during exposure to pulsed or continuous-wave ultraviolet light, Opt. Mater. 3, 209 (1994).
  51. E. H. Waller, S. Dix, J. Gutsche, A. Widera, and G. V. Freymann, Functional metallic microcomponents via liquid-phase multiphoton direct laser writing: A review, Micromachines 10, 827 (2019).
  52. M. Schmid, D. Ludescher, and H. Giessen, Optical properties of photoresists for femtosecond 3D printing: Refractive index, extinction, luminescence-dose dependence, aging, heat treatment and comparison between 1-photon and 2-photon exposure, Opt. Mater. Express 9, 4564 (2019).
  53. J. L. Sánchez Toural, V. Marzoa, R. Bernardo-Gavito, J. L. Pau, and D. Granados, Hands-on quantum sensing with NV-centers in diamonds, C 9, 16 (2023).
  54. J. J. Moré, in Numerical Analysis, Vol. 630, edited by G. A. Watson (Springer Berlin Heidelberg, Berlin, Heidelberg, 1978), p. 105, series Title: Lecture Notes in Mathematics.
  55. J. M. Schloss, J. F. Barry, M. J. Turner, and R. L. Walsworth, Simultaneous broadband vector magnetometry using solid-state spins, Phys. Rev. Appl. 10, 034044 (2018).
  56. A. Dréau, M. Lesik, L. Rondin, P. Spinicelli, O. Arcizet, J.-F. Roch, and V. Jacques, Avoiding power broadening in optically detected magnetic resonance of single NV defects for enhanced dc magnetic field sensitivity, Phys. Rev. B 84, 195204 (2011).
  57. N. Sekiguchi, M. Fushimi, A. Yoshimura, C. Shinei, M. Miyakawa, T. Taniguchi, T. Teraji, H. Abe, S. Onoda, T. Ohshima, M. Hatano, M. Sekino, and T. Iwasaki, Diamond quantum magnetometer with dc sensitivity of sub-10 pT Hz−1/2 toward measurement of biomagnetic field, Phys. Rev. Appl. 21, 064010 (2024).
  58. S. Ahmadi, H. A. R. El-Ella, J. O. B. Hansen, A. Huck, and U. L. Andersen, Pump-enhanced continuous-wave magnetometry using nitrogen-vacancy ensembles, Phys. Rev. Appl. 8, 034001 (2017).
  59. D. Allan, Statistics of atomic frequency standards, Proc. IEEE 54, 221 (1966).
  60. D. A. Van Baak, and G. Herold, Response of a lock-in amplifier to noise, Am. J. Phys. 82, 785 (2014).
  61. J. Zhang, T. Liu, L. Xu, G. Bian, P. Fan, M. Li, C. Xu, and H. Yuan, A pulsed lock-in method for DC ensemble nitrogen-vacancy center magnetometry, Diam. Relat. Mater. 125, 109035 (2022).
  62. W.-K. Quan, L. Liu, Q.-Y. Luo, X.-D. Liu, and J.-F. Wang, Fiber-coupled silicon carbide divacancy magnetometer and thermometer, Opt. Express 31, 15592 (2023).
  63. S.-C. Zhang, H.-B. Lin, Y. Dong, B. Du, X.-D. Gao, C. Yu, Z.-H. Feng, X.-D. Chen, G.-C. Guo, and F.-W. Sun, High-sensitivity and wide-bandwidth fiber-coupled diamond magnetometer with surface coating, Photonics Res. 10, 2191 (2022).
  64. A. K. Dmitriev, and A. K. Vershovskii, Concept of a microscale vector magnetic field sensor based on nitrogen-vacancy centers in diamond, J. Opt. Soc. Am. B 33, B1 (2016).
  65. S. M. Graham, A. T. M. A. Rahman, L. Munn, R. L. Patel, A. J. Newman, C. J. Stephen, G. Colston, A. Nikitin, A. M. Edmonds, D. J. Twitchen, M. L. Markham, and G. W. Morley, Fiber-coupled diamond magnetometry with an unshielded sensitivity of 30pT/Hz, Phys. Rev. Appl. 19, 044042 (2023).
  66. Y. Hatano, J. Shin, D. Nishitani, H. Iwatsuka, Y. Masuyama, H. Sugiyama, M. Ishii, S. Onoda, T. Ohshima, K. Arai, T. Iwasaki, and M. Hatano, Simultaneous thermometry and magnetometry using a fiber-coupled quantum diamond sensor, Appl. Phys. Lett. 118, 034001 (2021).
  67. Q. Liu, F. Xie, X. Peng, Y. Zhang, N. Wang, Y. Hu, L. Wang, Y. Liu, Y. Wang, S. Nie, H. Chen, J. Cheng, and Z. Wu, Closed-loop diamond quantum sensor for large range and high precision current measurement, IEEE Sens. J. 24, 4356 (2024).
  68. Q. Liu, F. Xie, X. Peng, Y. Hu, N. Wang, Y. Zhang, Y. Wang, L. Li, H. Chen, J. Cheng, and Z. Wu, Millimeter-scale temperature self-calibrated diamond-based quantum sensor for high-precision current sensing, Adv. Quantum Technol. 6, 2300210 (2023).
  69. S. M. Blakley, I. V. Fedotov, S. Y. Kilin, and A. M. Zheltikov, Room-temperature magnetic gradiometry with fiber-coupled nitrogen-vacancy centers in diamond, Opt. Lett. 40, 3727 (2015).
  70. H. Deguchi, T. Hayashi, H. Saito, Y. Nishibayashi, M. Teramoto, M. Fujiwara, H. Morishita, N. Mizuochi, and N. Tatsumi, Compact and portable quantum sensor module using diamond NV centers, Appl. Phys. Express 16, 062004 (2023).
  71. S. M. Blakley, I. V. Fedotov, L. V. Amitonova, E. E. Serebryannikov, E. Perez, S. Y. Kilin, and A. M. Zheltikov, Fiber-optic vectorial magnetic-field gradiometry by a spatiotemporal differential optical detection of magnetic resonance in nitrogen-vacancy centers in diamond, Opt. Lett. 41, 2057 (2016).
  72. S. Johansson, D. Lönard, I. Cardoso Barbosa, J. Gutsche, J. Witzenrath, and A. Widera, Data for: “Miniaturized magnetic-field sensor based on nitrogen-vacancy centers”, 2025, https://doi.org/10.5281/zenodo.16410952
  73. D. Lönard, Microscope Experiment Control Application, 2025, https://gitlab.rlp.net/agwidera/public/waveguide-control-python
  74. A. Landowski, D. Zepp, S. Wingerter, G. von Freymann, and A. Widera, Direct laser written polymer waveguides with out of plane couplers for optical chips, APL Photonics 2, 106102 (2017).
  75. G. Balasubramanian, I. Y. Chan, R. Kolesov, M. Al-Hmoud, J. Tisler, C. Shin, C. Kim, A. Wojcik, P. R. Hemmer, A. Krueger, T. Hanke, A. Leitenstorfer, R. Bratschitsch, F. Jelezko, and J. Wrachtrup, Nanoscale imaging magnetometry with diamond spins under ambient conditions, Nature 455, 648 (2008).
  76. Y. Wang, R. Zhang, Y. Yang, Q. Wu, Z. Yu, and B. Chen, Orientation determination of nitrogen-vacancy center in diamond using a static magnetic field, Chin. Phys. B 32, 070301 (2023).
  77. W. H. Press, S. A. Teukolsky, W. T. Vetterling, and B. P. Flannery, Numerical Recipes - The Art of Scientific Computing - 3rd Edition (Cambridge University Press, Cambridge, 2007).

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Phys. Rev. Applied 24, 054078– Published 26 November, 2025
  • Received 4 February 2025
  • Revised 23 July 2025
  • Accepted 24 October 2025
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