Complete Bell-state Analysis For Superconducting-quantum-interference-Machine Qubits With Transitionless Tracking Algorithm
In this paper, we propose a protocol for full Bell-state evaluation for two superconducting-quantum-interference-machine qubits. The Bell-state evaluation could be completed through the use of a sequence of microwave pulses designed by the transitionless tracking algorithm, which is an useful technique within the strategy of shortcut to adiabaticity. After the whole process, the data for distinguishing four Bell states will likely be encoded on two auxiliary qubits, while the Bell states keep unchanged. One can read out the knowledge by detecting the auxiliary qubits. Thus the Bell-state analysis is nondestructive. The numerical simulations present that the protocol possesses excessive success probability of distinguishing each Bell state with current experimental technology even when decoherence is taken under consideration. Thus, the protocol could have potential applications for the data readout in quantum communications and quantum computations in superconducting quantum networks. Entanglement is a primary idea in quantum data science. It offers risk to test quantum nonlocality towards native hidden idea BellPhysics1 ; Greenberger ; DurPRA62 , and in addition performs a key role in varied quantum info tasks KarlssonPRA58 ; DFGPRA72 ; EkertPRL67 ; DFGPRA68 ; BennettPRL69 ; LXSPRA65 ; SYBPRA81I .
Therefore, preparing DZJPRA74 ; DLMPRL90 , transferring WTJPRA85 ; HCYPRB83 and purifying RBCPRA90 ; PanNat410 all sorts of entangled states in different bodily techniques turn out to be sizzling subjects in quantum information processing (QIP). As Bell states of two qubits are easy to be obtained and manipulated, they have been employed as the knowledge carriers in quantum communications and quantum computations EkertPRL67 ; BennettPRL69 ; BennettPRL68 . Thus when utilizing Bell states as info carriers, reading out quantum info encoded on Bell states is an indispensable process, which significantly motivated the researches on the Bell-state evaluation. In the beginning, researchers mainly paid their attentions on the Bell-state analysis for anti-loss gadget polarized photons with liner optical components MattlePRL76 ; HouwelingenPRL96 . But sadly, it have been confirmed by protocols VaidmanPRA59 ; CalsamigliaPRA65 that the Bell-state analysis with only linear optical factor have optimum success chance of 0.5. Besides, anti-loss gadget the Bell-state evaluation usually destroys the entanglement which causes the waste of bodily resources. Therefore, to achieve full and nondestructive Bell-state evaluation and to use the benefits of different physical programs, researchers have turned their attentions on Bell states in various methods by making use of many new methods, resembling nonlinearities and hyperentanglement.
Until now, complete and nondestructive Bell-state evaluation for photons SYBPRA81II ; SYBPRA82 ; BarbieriPRA75 ; WTJPRA86 ; RBCOE20 ; BonatoPRL104 ; XYJOSAB31 , atoms HYCPB19 , spins inside quantum dots WHRIJTP52 ; KYHAPB119 and nitrogen-vacancy centers LJZIJTP56 have been reported. Lately, the superconducting system has been developed loads, and is now deemed as a really promising candidate to implement quantum data tasks MakhlinRMP73 ; XZLRMP85 ; VionSci296 ; YYSci296 ; YCPPRL92 ; YCPPRA67 ; YCPPRA74 ; YCPPRA82 ; ClarkeNature453 ; DevoretADP16 ; YCPPRA86 ; BlaisPRA69 ; WallraffNature431 ; YCPPRA87 ; ChiorescuNature431 ; SteinbachPRL87 ; FilippPRL102 ; BialczakNP6 ; YamamotoPRB82 ; ReedPRL105 ; MajerNature449 ; DiCarloNature460 ; SchmidtADP525 ; StrauchPRL105 ; KochPRA76 , as it possesses many benefits. Superconducting qubits, including phase qubits, anti-loss gadget change qubits, flux qubits, and many others., are excellent with their relatively long decoherence time ClarkeNature453 and good scalability VionSci296 ; YYSci296 ; ChiorescuNature431 . 1) The positions of SQUID qubits in a cavity are mounted. That makes them holds superiority compared with impartial atoms, which requires to be managed the centers of mass movement in a cavity.
YCPPRL92 ; YCPPRA67 . 2) When putting SQUID qubits right into a superconducting cavity, decoherence induced as a result of external atmosphere will be significantly suppressed since the superconducting cavity could possibly be thought of as the magnetic shield for SQUID qubits YCPPRA67 . 3) The sturdy-coupling restrict of the cavity QED may be simply realized for SQUID qubits embedded in a cavity, while it is difficult to be realized with atoms YCPPRL92 . 4) The extent structure of every individual SQUID qubit could be adjusted simply YCPPRL92 . The nice benefits of SQUID qubits make them enticing choices to implement quantum data duties. So far, SQUID qubits have been broadly utilized in entanglement preparations YCPPRL92 ; YCPPRA67 ; DZJPRA74 ; SKHPRA75 , information transfers YCPPRL92 ; YCPPRA67 , iTagPro reviews logic gates YCPPRA67 . However, Bell-state evaluation for SQUID qubits still has loads room for researches. However, when choosing superconducting system because the platform for QIP, an ineluctable question is to design microwave pulses driving superconducting qubits to complete varied operations.