Realization of squeezing of single photons and a dynamic squeezing gate -- linear and nonlinear feedforward --

Transcription

1 Isaac Newton Institute for Mathematical Sciences QCE seminar, July 22, 2014 Realization of squeezing of single photons and a dynamic squeezing gate -- linear and nonlinear feedforward -- Akira Furusawa Department of Applied Physics The University of Tokyo

2 Collaborators A. Furusawa Univ. of Tokyo J. Yoshikawa, S. Yokoyama, K. Miyata, K. Makino, M. Fuwa, H. Ogawa, T. Kaji, Y. Hashimoto, H. Odan, T. Serikawa, Y. Shiozawa, M. Taguchi, T. Tohyama, R. Nakamura, K. Muramoto, S. Suzuki, S. C. Armstrong (ANU), G. Masada (Tamagawa), J. Meinecke (Bristol) P. van Loock (Mainz), R. Filip (Palacky), L. Mista (Palacky), P. Marek (Palacky), J. L. O Brien (Bristol), A. Politi (Southampton), E. H. Huntington (ADFA), T. Ralph (UQ), H. Wiseman (GU), N. Menicucci (Sydney), H. Yonezawa (ADFA), S. Takeda (IMS)

3 Quantum noise reduction with squeezed light

4 Quantum noise reduction with squeezed light linear feedforward

5 Quantum noise reduction with nonclassical state of light linear and nonlinear feedforward

6 Realization Quantum of noise universal reduction quantum Quantum state of light p information with nonclassical processing state of light linear feedforward x We need at least one non-linear gate p Linear (Gaussian) operations x p Displacement Squeezing Rotation x p x S. Lloyd and S. L. Braunstein, PRL 82, 1784 (1999) Non-linear (non-gaussian) operations Cubic phase gate nonlinear feedforward p x

7 Squeezing of single photons and Schrödinger cat states linear feedforward for non-gaussian states Y. Miwa, J. Yoshikawa, N. Iwata, M. Endo, P. Marek, R. Filip, P. van Loock, and A. Furusawa, Phys. Rev. Lett. 113, (2014)

8 High-fidelity universal squeezer with gate teleportation Gate teleportation BS X p-measurement Input T tunability of squeezing level with T Displace in p Feedforward Beam Splitter OPO linear feedforward Squeezed vacuum p x R. Filip, P. Marek, and U. L. Andersen, PRA 71, (2005)

9 Experimental set-up Input Squeezed Light OPO-2 Output LO OPO-1 SC FC-1 FC-2 APD BS (T) 50%R LO ~12m 99.4%R EOM HD-2 Oscilloscope Single Photon Source Alternative 3%R HD-1 Classical Channel Squeezer Trigger Signal OPO-1 CSS Source FC-1 FC-2 APD Y. Miwa et al., PRL 113, (2014)

10 Squeezing of a single photon From particles to waves X BS Y. Miwa et al., PRL 113, (2014) without any correction!!

11 Squeezing of a single photon From particles to waves X BS amplitude phase [/ rad] Y. Miwa et al., PRL 113, (2014) without any correction!!

12 Squeezing of Schrödinger cat From waves to particles Probability Photon number X BS Probability Photon number without any correction!! Y. Miwa et al., PRL 113, (2014)

13 Quantum Non-Demolition (QND) interaction QND gate CV-CNOT gate (G=1) p SQZ BS BS QND SQZ x

14 QND interaction with universal squeezers B Universal squeezer Mode 1 Mode 2 QND gate -4.2 db of squeezing A Universal squeezer

15 Experimental results After QND Before QND Inputs Outputs Theoretical values with finite squeezing of ancillae: -4.9dB J. Yoshikawa et al., Phys. Rev. Lett. 101, (2008)

16 Now working on QND on single photons

17 Dynamic squeezing gate For realization of nonlinear quantum gates nonlinear feedforward K. Miyata, H. Ogawa, H. Yonezawa, P. Marek, R. Filip, and A. Furusawa, in preparation.

18 Realization Quantum of noise universal reduction quantum Quantum state of light p information with nonclassical processing state of light linear feedforward x We need at least one non-linear gate p Linear (Gaussian) operations x p Displacement Squeezing Rotation x p x S. Lloyd and S. L. Braunstein, PRL 82, 1784 (1999) Non-linear (non-gaussian) operations Cubic phase gate nonlinear feedforward p x

19 Cubic phase gate Schrödinger picture Heisenberg picture

20 Can you make this conversion by a nonlinear crystal at single photon level? No! state preparation with strong light and then make a gate teleportation

21 Realization of a cubic phase gate with gate teleportation Schrödinger picture Gottesman et al. PRA 64, (2001) Input nonlinear feedforward Output q cubic phase state QND gate Gate teleportation

22 Realization of a cubic phase gate with gate teleportation Heisenberg picture Gottesman et al. PRA 64, (2001) Input nonlinear feedforward Output q cubic phase state QND gate

23 Cubic phase state Schrödinger picture Heisenberg picture p p p x Simulation finite squeezing x Simulation 0 & 1 photon x Experiment 0 & 1 photon

24 Realization of a cubic phase gate with gate teleportation Heisenberg picture Gottesman et al. PRA 64, (2001) Input nonlinear feedforward Output Too complicated!! q cubic phase state QND gate P. Marek et al. PRA 84, (2011)

25 The simplest scheme of Nonlinearity a cubic (Non-Gaussianity) phase gate comes from nonlinear feedforward cubic phase state squeezed vacuum Nonclassicality comes from nonclassical states input Quantum noise reduction output with nonclassical p-displacement state of light

26 The simplest scheme of a cubic phase gate cubic phase state squeezed vacuum input p-displacement output

27 The simplest scheme of a cubic phase gate cubic phase state Nonlinear feedforward squeezed vacuum input p-displacement output Dynamic squeezing gate

28 Dynamic squeezing gate cubic phase state Nonlinear feedforward squeezed vacuum input p p-displacement output 1 MHz ~ 5MHz x

29 Nonlinear feedforward cubic +, )*!"#$%&!"#$%'!"#$%( &-./ &-./ &-./ '0* '0* '0* (1* squeezed vacuum input p ~ 5MHz x p-displacement /,+ +,-. output 1 MHz ;$- %()*!"#23!&4!5&6-1 )$%! " 5678)8 )* 234 +,-. /,+ )9%! " %()* 78/%9: -0 <$-

30 Nonlinear feedforward +,!"#$%& &-./ '0* )*!"#$%'!"#$%( &-./ &-./ '0* '0* (1* /,+ +,-. ;$- %()*!"#23!&4!5&6-1 )$%! " 5678)8 )* 234 +,-. /,+ )9%! " %()* 78/%9: -0 <$-

31 Nonlinear feedforward cubic squeezed vacuum -amp 3;: ()*+,-(&.(/&0 input p p-displacement output 5// ! " <> 8? ~ 5MHz x &" 88/ 89/! "./ 012/34 6E +<%=>? )&@)A&B!"#$%&'#()*+,- 5C67 88/ 53/ 5C67! " :; / 89/ 3D/! " :;04.4./!AB

32 Nonlinear feedforward -amp 5//67 &" 88/ 89/! "./ 012/34 6E +<%=>? 5C67 88/ 53/ 5C67! " :; / 89/ 3D/!./ " :;04.4!AB

33 2 2 1MHz 0 0 p ~ 5MHz x Input amplitude squeezed vacuum anti sqz. angle (deg) input cubic p x ~ 5MHz 0 10 p-displacement output p 45º x Output amplitudes Variances (db) Time (us) x p x p 45 anti sqz. level (db) sqz. level (db) MHz Time (us)

34 2 0 p x anti sqz. angle (deg) cubic squeezed vacuum input p x ~ 5MHz p-displacement output x p anti sqz. level (db) x p sqz. level (db) Time (us) 1 MHz

35 The simplest scheme of a cubic phase gate cubic phase state squeezed vacuum input p-displacement output

36 Both photons are resonant to the OPO cavity.

37 Only orange photons are resonant to the OPO cavity.

38

39 The quantum teleportation chip

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