Generation and Reconstruction of Propagating Quantum Microwaves Ling

Generation and Reconstruction of Propagating Quantum Microwaves Ling Zhong, August, 2015 ( August) Walther-Meissner-Institut, TU München Nanosystems Initiative Munich (September ) Yale University, Steve Lamoreaux, Ben Brubaker

Propagating quantum microwaves Superconducting circuits artificial atom qubit quantum harmonic oscillator |2> 75 µm |1> |0> m 10 m Emit propagating quantum microwave states Quantum computing http: //news. discovery. com 75 µm Quantum communication http: //www. nii. ac. jp Quantum illumination http: //www. srh. noaa. gov 2

Quantum communication Problem: transferring an arbitrary quantum state from Alice to Bob http: //coloringmypages. tk www. easydrawingtutorials. com http: //box-cat. com/ 3

Quantum communication Problem: transferring an arbitrary quantum state from Alice to Bob Solution: 1. Direct transport www. clipartpanda. com Can be lossy and slow, sometimes impossible. 4

Quantum communication Problem: transferring an arbitrary quantum state from Alice to Bob Solution: 2. Measurement and reconstruction www. penguincomputel. com Impossible. 5

Quantum communication Problem: transferring an arbitrary quantum state from Alice to Bob Solution: 3. Quantum teleportation - Quantum entanglement Bell measurement Classical communication Linear transformation www. scifiideas. com 6

Propagating quantum microwave teleportation Alice Bob 7

Overview Josephson parametric amplifier (JPA) Path entanglement § Amplification § Noise § Squeezing Linear transformation Commutation relation between Squeeze and displacement operators State detection Scalability of the setup § Controlling of multiple JPAs § G(2) correlation time § Scale to remote state preparation and teleportation 8

Overview Josephson parametric amplifier (JPA) Path entanglement § Amplification § Noise § Squeezing Linear transformation Commutation relation between Squeeze and displacement operators State detection Scalability of the setup § Controlling of multiple JPAs § G(2) correlation time § Scale to remote state preparation and teleportation 9

Josephson parametric amplifier (JPA) Flux-driven Josephson parametric amplifier (JPA) Squeeze operator T. Yamamoto et al. , APL 93, 042510 (2008) 10

State detection Pump Dual-path detector Signal Squeezed vacuum states Sample stage 11

State detection Pump Dual-path detector Signal Squeezed coherent states Sample stage 12

What to expect? Squeezed coherent state p p q q p Anti-squeeze angle p Coherent state angle 13

Squeezed coherent states Pump Signal 4. 3 d. B squeezing L. Zhong et al. , NJP 15, 125013 (2013) 14

Squeezed coherent states Coherent state angle 8 Vacuum 4 12 q 0 Antisqueeze angle q 0 -4 -8 -8 -4 L. Zhong et al. , NJP 15, 125013 (2013) 0 p 4 8 -12 0 p 12 aligned 15

Squeezed coherent states Coherent state angle 8 Vacuum Antisqueeze angle 4 10 q 0 0 -4 -10 -8 -4 L. Zhong et al. , NJP 15, 125013 (2013) 0 p 4 8 0 p 10 perpendicular 16

Squeezed coherent states Coherent state angle 8 4 q 0 -4 Squeezed vacuum Antisqueeze angle -8 -8 -4 L. Zhong et al. , NJP 15, 125013 (2013) 0 p 4 8 17

Overview Josephson parametric amplifier (JPA) Path entanglement § Amplification § Noise § Squeezing Linear transformation Commutation relation between Squeeze and displacement operators State detection Scalability of the setup § Controlling of multiple JPAs § G(2) correlation time § Scale to remote state preparation and teleportation 18

Displacement operation with power linear transmissivity power linear reflectivity Displacement operator M. G. A. Paris, Phys. Letter. A. 217, 78 -80 (1996) 19

State detection 20

State detection Pump Signal Displaced squeezed states 21

What to expect? Squeezed coherent states Displaced squeezed states 22

Displaced squeezed states Pump Displace 23

Displaced squeezed states Pump Displace 24

Displaced squeezed states The hybrid ring input states Experimental coherent squeezed states The hybrid ring output states 25

Displaced squeezed states The hybrid ring input states Experimental coherent squeezed states The hybrid ring output states (based on the beam splitter relation) Previous work: Maximum negativity 0. 55 3. 2 d. B TMS EPM et al. , PRL 109, 250502 (2012) 26

Summary 1. Dual-path state reconstruction 2. Squeezing with JPA 3. Displacement of squeezed state 4. Path entanglement 27

Outlook Current status • Linear transformation • Two-mode squeezed state In the future • Pure two-mode squeezed state • G(2) correlation time • Remote state preparation • Quantum teleportation 28

SQC group A. Baust P. Eder J. Goetz M. Häberlein F. Wulschner Edwar Xie L. Zhong M. Betzenbichler S. Pogorzalek Theory R. Di Candia (Bilbao) M. Sanz (Bilbao) Mikel Sanz (Bilbao) E. Solano (Bilbao) JPA sample K. Inomata (NEC) T. Yamamoto (NEC) Y. Nakamura (U. Tokyo) r fo n u io o y nt k n tte a Th ur a yo K. Fedorov E. P. Menzel H. Hübl F. Deppe A. Marx R. Gross 29