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Strong suppression of shot noise in a feedback-controlled single-electron transistor


Feedback control of quantum mechanical systems is rapidly attracting attention not only due to fundamental questions about quantum measurements1, but also because of its novel applications in many fields in physics. Quantum control has been studied intensively in quantum optics1,2 but progress has recently been made in the control of solid-state qubits3,4,5 as well. In quantum transport only a few active6,7,8 and passive9,10,11 feedback experiments have been realized on the level of single electrons, although theoretical proposals12,13,14 exist. Here we demonstrate the suppression of shot noise in a single-electron transistor using an exclusively electronic closed-loop feedback to monitor and adjust the counting statistics6,15,16,17,18,19,20. With increasing feedback response we observe a stronger suppression and faster freezing of charge current fluctuations. Our technique is analogous to the generation of squeezed light with in-loop photodetection1,21,22 as used in quantum optics. Sub-Poisson single-electron sources will pave the way for high-precision measurements in quantum transport similar to optical or optomechanical23 equivalents.

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Figure 1: Feedback set-up.
Figure 2: Detailed feedback processing.
Figure 3: Stationary and feedback distributions.
Figure 4: Feedback-dependent cumulants of the charge fluctuations.


  1. Wiseman, H. M. Quantum Measurement and Control (Cambridge Univ. Press, 2009).

    Book  Google Scholar 

  2. Serafini, A. Feedback control of quantum optics: an overview of experimental breakthroughs and areas of application. ISRN Optics 2012, 275016 (2012).

    Article  Google Scholar 

  3. Bluhm, H., Foletti, S., Mahalu, D., Umansky, V. & Yacoby, A. Enhancing the coherence of a spin qubit by operating it as a feedback loop that controls its nuclear spin bath. Phys. Rev. Lett. 105, 216803 (2010).

    Article  Google Scholar 

  4. Vijay, R. et al. Stabilizing Rabi oscillations in a superconducting qubit using quantum feedback. Nature 490, 77–80 (2012).

    Article  CAS  Google Scholar 

  5. Blok, M. S. et al. Manipulating a qubit through the backaction of sequential partial measurements and real-time feedback. Nat. Phys. 10, 189–193 (2014).

    Article  CAS  Google Scholar 

  6. Chida, K., Nishiguchi, K., Yamahata, G., Tanaka, H. & Fujiwara, A. Thermal-noise suppression in nano-scale Si field-effect transistors by feedback control based on single-electron detection. Appl. Phys. Lett. 107, 073110 (2015).

    Article  Google Scholar 

  7. Koski, J. V., Maisi, V. F. Pekola, J. P. & Averin, D. V. Experimental realization of a Szilard engine with a single electron. Proc. Natl Acad. Sci. USA 111, 13786–13789 (2014).

    Article  CAS  Google Scholar 

  8. Hofmann, A. et al. Equilibrium free energy measurement of a confined electron driven out of equilibrium. Phys. Rev. B. 93, 035425 (2016).

    Article  Google Scholar 

  9. Fricke, L. et al. Quantized current source with mesoscopic feedback. Phys. Rev. B 83, 193306 (2011).

    Article  Google Scholar 

  10. Thierschmann, H. et al. Three-terminal energy harvester with coupled quantum dots. Nat. Nanotech. 10, 854–858 (2015).

    Article  CAS  Google Scholar 

  11. Koski, J. V., Kutvonen, A., Khaymovich, I. M., Ala-Nissila, T. & Pekola, J. P. On-chip Maxwell's demon as an information-powered refrigerator. Phys. Rev. Lett. 115, 260602 (2015).

    Article  CAS  Google Scholar 

  12. Brandes, T. Feedback control of quantum transport. Phys. Rev. Lett. 105, 06060 (2010).

    Article  Google Scholar 

  13. Kießlich, G., Schaller, G., Emary, C. & Brandes, T. Charge qubit purification by an electronic feedback loop. Phys. Rev. Lett. 107, 050501 (2011).

    Article  Google Scholar 

  14. Emary, C. & Gough, J. Coherent feedback control in quantum transport. Phys. Rev. B 90, 205436 (2014).

    Article  Google Scholar 

  15. Bagrets, D. A. & Nazarov, Yu. V. Full counting statistics of charge transfer in Coulomb blockade systems. Phys. Rev. B 67, 085316 (2003).

    Article  Google Scholar 

  16. Lu, W., Ji, Z., Pfeiffer, L., West, K. W., Rimberg, A. J. Real-time detection of electron tunneling in a quantum dot. Nature 423, 422–425 (2003).

    Article  CAS  Google Scholar 

  17. Bylander, J., Duty, T. & Delsing, P. Current measurement by real-time counting of single electrons. Nature 434, 361–364 (2005).

    Article  CAS  Google Scholar 

  18. Gustavsson, S. et al. Counting statistics of single-electron transport in a quantum dot. Phys Rev Lett. 96, 076605 (2006).

    Article  CAS  Google Scholar 

  19. Flindt, C. et al. Universal oscillations in counting statistics. Proc. Natl Acad. Sci. USA 106, 10116–10119 (2009).

    Article  CAS  Google Scholar 

  20. Fricke, L. et al. Self-referenced single-electron quantized current source. Phys. Rev. Lett. 112, 226803 (2014).

    Article  Google Scholar 

  21. Walker, J. G. & Jakeman, E. Optical dead time effects and sub Poissonion photo-electron counting statistics. Proc. SPIE 492, 274–277 (1985).

    Article  Google Scholar 

  22. Machida, S. & Yamamoto, Y. Observation of sub-poissonian photoelectron statistics in a negative feedback semiconductor laser. Opt. Commun. 57, 290–296 (1986).

    Article  CAS  Google Scholar 

  23. Wollman, E. E. et al. Quantum squeezing of motion in a mechanical resonator. Science 349, 952–955 (2015).

    Article  CAS  Google Scholar 

  24. Schottky, W. Über spontane Stromschwankungen in verschiedenen Elektrizitätsleitern. Ann. Phys. 362, 541–567 (1918).

    Article  Google Scholar 

  25. Blanter, Ya. M. & Büttiker, M. Shot noise in mesoscopic conductors. Phys. Rep. 336, 1–166 (2000).

    Article  CAS  Google Scholar 

  26. Landauer, R. Condensed-matter physics: the noise is the signal. Nature 392, 658–659 (1998).

    Article  CAS  Google Scholar 

  27. Pekola, J. P. et al. Single-electron current sources: toward a refined definition of the ampere. Rev. Mod. Phys. 85, 1421–1472 (2013).

    Article  Google Scholar 

  28. Cassidy, M. C. et al. Single shot charge detection using a radio-frequency quantum point contact. Appl. Phys. Lett. 91, 222104 (2007).

    Article  Google Scholar 

  29. Wulf, M. Error accounting algorithm for electron counting experiments. Phys. Rev. B 87, 035312 (2013).

    Article  Google Scholar 

  30. Strasberg, P., Schaller, G., Brandes, T. & Esposito, M. Thermodynamics of a physical model implementing a maxwell demon. Phys. Rev. Lett. 110, 040601 (2013).

    Article  Google Scholar 

  31. Sothmann, B., Sánchez, R. & Jordan, A. N. Thermoelectric energy harvesting with quantum dots. Nanotechnology 26, 032001 (2015).

    Article  CAS  Google Scholar 

  32. Maire, N., Hohls, F., Lüdtke, T., Pierz, K. & Haug, R. J. Noise at a Fermi-edge singularity in self-assembled InAs quantum dots. Phys. Rev. B 75, 233304 (2007).

    Article  Google Scholar 

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We thank G. Haack for the valuable discussions. This work was financially supported by the DFG GRK 1991, QUEST (T.W, J.C.B., E.P.R. and R.J.H.) and DFG SFB 910, GRK 1558 (P.S. and T.B.).

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T.W. carried out the experiments, analysed the data and wrote the manuscript. J.C.B. and T.W. fabricated the device. E.P.R. provided the wafer material. P.S and T.B. provided theory support and supplied Supplementary Material. R.J.H. supervised the research. All authors discussed the results and contributed to editing the manuscript.

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Correspondence to Timo Wagner.

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The authors declare no competing financial interests.

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Wagner, T., Strasberg, P., Bayer, J. et al. Strong suppression of shot noise in a feedback-controlled single-electron transistor. Nature Nanotech 12, 218–222 (2017).

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