This paper proposes schemes for generating multiple-photon and multiple-atom cluster states, respectively. The schemes are based on the cavity input-output process and atomic or photonic states measurement, and the su...This paper proposes schemes for generating multiple-photon and multiple-atom cluster states, respectively. The schemes are based on the cavity input-output process and atomic or photonic states measurement, and the successful probabilities approach unity in the ideal case. The numerical simulations show that the produced multiple-particle cluster states have high fidelity even if the Lamb-Dicke condition is not satisfied. Some practical imperfections, such as atomic spontaneous emission and output coupling inefficiency, only decrease the success probability but exert no influence on the fidelity of generated multiple-particle cluster states. From the experimental point of view, smaller operation number and lack of need for individual addressing keeps the schemes easy to implement. These schemes may offer a promising approach to the generation of a large-scale cluster state.展开更多
A scheme is presented to generate atomic entanglement by detecting the transmission spectrum of a coupled- cavity system. In the scheme, two 3-level atoms are trapped in separate cavities coupled by a short optical fi...A scheme is presented to generate atomic entanglement by detecting the transmission spectrum of a coupled- cavity system. In the scheme, two 3-level atoms are trapped in separate cavities coupled by a short optical fiber, and the atomic entanglement could be realized in a heralded way by detecting the transmission spectrum of the coupled-cavity system.展开更多
This paper proposes a scheme to teleport an arbitrary mixture of diagonal states of multiqutrit via classical correlation and classical communication. To teleport an arbitrary mixture of diagonal states of N qutrits, ...This paper proposes a scheme to teleport an arbitrary mixture of diagonal states of multiqutrit via classical correlation and classical communication. To teleport an arbitrary mixture of diagonal states of N qutrits, N classically correlated pairs of two qutrits are used as channel. The sender (Alice) makes Fourier transform and conditional gate (i.e., XOR(3) gate) on her qutrits and does measurement in appropriate computation bases. Then she sends N ctrits to the receiver (Bob). Based on the received information, Bob performs the corresponding unitary transformation on his qutrits and obtains the teleported state. Teleportation of an arbitrary mixture of diagonal states of multiqudit is also discussed.展开更多
A terahertz (THz) waveguide using a metallic nanoslit whose width is much smaller than the skin depth is analytically investigated. By taking some important physical properties into account, we derive a simple, yet ...A terahertz (THz) waveguide using a metallic nanoslit whose width is much smaller than the skin depth is analytically investigated. By taking some important physical properties into account, we derive a simple, yet accurate, expression for the effective index. We also study the changes in modal field and the attenuation coefficient in the whole THz region, and find some interesting physical properties. Finally, we verify that these theoretical analyses coincide with the rigorous nmnerical simulations. This research can be useful for various applications of THz waveguides made of metallic nanoslits.展开更多
This paper proposes a scheme for implementing teleportation of an entangled state of two trapped atoms through adiabatic passage and photonic interference. The scheme is robust against certain noise such as atomic spo...This paper proposes a scheme for implementing teleportation of an entangled state of two trapped atoms through adiabatic passage and photonic interference. The scheme is robust against certain noise such as atomic spontaneous emission and the detector inefficiency.展开更多
This paper proposes a scalable scheme to generate n-atom GHZ states and cluster states by using the basic building block, i.e., a weak coherent optical pulse [α) being reflected successively from a single-atom cavit...This paper proposes a scalable scheme to generate n-atom GHZ states and cluster states by using the basic building block, i.e., a weak coherent optical pulse [α) being reflected successively from a single-atom cavity. In the schemes, coherent state of light is used instead of single photon source, homodyne measurement on coherent light is done kastead of single photon detection, and no need for individually addressing keeps the schemes easy to implement from the experimental point of view. The successful probabilities of our protocols approach unity in the ideal case.展开更多
This paper presents a direct implementation scheme of the non-local multi-qubit controlled phase gate by using optical fibres and adiabatic passage. The smaller operation number for implementing the multi-qubit contro...This paper presents a direct implementation scheme of the non-local multi-qubit controlled phase gate by using optical fibres and adiabatic passage. The smaller operation number for implementing the multi-qubit controlled phase gate and needlessness for addressing individually save physical resource and lower the difficulties of experiment. Mean- while, the scheme is immune from some decoherence effects such as the atomic spontaneous emission and fibre loss. In principle, it is scalable.展开更多
We propose a scheme for preparing multiple-photon GHZ state via cavity-assisted interaction. There are n-pair single-photon pulses successively injected and reflected from two sides of the cavity, which traps one atom...We propose a scheme for preparing multiple-photon GHZ state via cavity-assisted interaction. There are n-pair single-photon pulses successively injected and reflected from two sides of the cavity, which traps one atom. After the atomic state is measured, a 2n-photon GHZ state is produced. In the ideal case, the successful probability of the scheme is close to unity.展开更多
We present a scheme for the quantum storage of single photons using electromagnetically induced transparency(EIT)in a low-finesse optical cavity,assisted by state-selected spontaneous atomic emission.Mediated by the d...We present a scheme for the quantum storage of single photons using electromagnetically induced transparency(EIT)in a low-finesse optical cavity,assisted by state-selected spontaneous atomic emission.Mediated by the dark mode of cavity EIT,the destructive quantum interference between the cavity input-output channel and state-selected atomic spontaneous emission leads to strong absorption of single photons with unknown arrival time and pulse shapes.We discuss the application of this phenomenon to photon counting using stored light.展开更多
Global change in the dispersive behavior of terahertz (THz) plasmons on metal wires with wide radii ranging from 5 nm to 0.5 mm is systematically investigated. Through rigorous numerical calculations, we find that t...Global change in the dispersive behavior of terahertz (THz) plasmons on metal wires with wide radii ranging from 5 nm to 0.5 mm is systematically investigated. Through rigorous numerical calculations, we find that the dispersion of a metal wire with a radius of 5 nm increases by about 4-6 orders of magnitude compared with the case of a metallic wire with a radius of 0.5 mm. Zero-dispersion points appear when the frequency is lower than 3 THz, and the positions of the zero-dispersion points can shift with the frequency. Finally, we provide an explicit expression that agrees verv well with the numerical calculations.展开更多
We analyze the transport property of a single photon in a one-dimensional coupled resonator waveguide coupled with a Λ-type emitter assisted by an additional cavity. The reflection and transmission coefficients of th...We analyze the transport property of a single photon in a one-dimensional coupled resonator waveguide coupled with a Λ-type emitter assisted by an additional cavity. The reflection and transmission coefficients of the inserted photon are obtained by the stationary theory. It is shown that the polarization state of the inserted photon can be converted with high efficiency. This study may inspire single-photon devices for scalable quantum memory.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No 10574022)the Natural Science Foundation of Fujian Province of China (Grant Nos 2007J0002 and 2006J0230)Funds of Education Committee of Fujian Province of China (Grant No JB05334)
文摘This paper proposes schemes for generating multiple-photon and multiple-atom cluster states, respectively. The schemes are based on the cavity input-output process and atomic or photonic states measurement, and the successful probabilities approach unity in the ideal case. The numerical simulations show that the produced multiple-particle cluster states have high fidelity even if the Lamb-Dicke condition is not satisfied. Some practical imperfections, such as atomic spontaneous emission and output coupling inefficiency, only decrease the success probability but exert no influence on the fidelity of generated multiple-particle cluster states. From the experimental point of view, smaller operation number and lack of need for individual addressing keeps the schemes easy to implement. These schemes may offer a promising approach to the generation of a large-scale cluster state.
基金supported by the National Natural Sciences Foundation of China(Grant Nos.11204080,11274112,91321101,and 61275215)the Fundamental Research Funds for the Central Universities(Grant No.WM1313003)
文摘A scheme is presented to generate atomic entanglement by detecting the transmission spectrum of a coupled- cavity system. In the scheme, two 3-level atoms are trapped in separate cavities coupled by a short optical fiber, and the atomic entanglement could be realized in a heralded way by detecting the transmission spectrum of the coupled-cavity system.
基金Project supported by the National Natural Science Foundation of China(Grant No10574022)the Natural Science Foundation of Fujian Province of China(Grant Nos2006J0230 and A0410016)Funds of Education Committee of Fujian Province,China(Grant No JB05334)
文摘This paper proposes a scheme to teleport an arbitrary mixture of diagonal states of multiqutrit via classical correlation and classical communication. To teleport an arbitrary mixture of diagonal states of N qutrits, N classically correlated pairs of two qutrits are used as channel. The sender (Alice) makes Fourier transform and conditional gate (i.e., XOR(3) gate) on her qutrits and does measurement in appropriate computation bases. Then she sends N ctrits to the receiver (Bob). Based on the received information, Bob performs the corresponding unitary transformation on his qutrits and obtains the teleported state. Teleportation of an arbitrary mixture of diagonal states of multiqudit is also discussed.
基金supported by the National Natural Sciences Foundation of China under Grants Nos.11347155,91321101,11474092,11274112,and 11204080
文摘A terahertz (THz) waveguide using a metallic nanoslit whose width is much smaller than the skin depth is analytically investigated. By taking some important physical properties into account, we derive a simple, yet accurate, expression for the effective index. We also study the changes in modal field and the attenuation coefficient in the whole THz region, and find some interesting physical properties. Finally, we verify that these theoretical analyses coincide with the rigorous nmnerical simulations. This research can be useful for various applications of THz waveguides made of metallic nanoslits.
基金Protect supported by the National Natural Science Foundation of China (Grant No 10574022), the Natural Science Foundation of Fujian Province, China (Grant Nos A0410016 and 2006J0230) and the Funds of Educational Committee of Fujian Province, China (Grant No JB05334 and JB05340).
文摘This paper proposes a scheme for implementing teleportation of an entangled state of two trapped atoms through adiabatic passage and photonic interference. The scheme is robust against certain noise such as atomic spontaneous emission and the detector inefficiency.
基金Project supported by the National Natural Science Foundation of China (Grant No 10574022)the Natural Science Foundation of Fujian Province of China (Grant Nos 2007J0002 and 2006J0230)the Foundation for Universities in Fujian Province (Grant No 2007F5041)
文摘This paper proposes a scalable scheme to generate n-atom GHZ states and cluster states by using the basic building block, i.e., a weak coherent optical pulse [α) being reflected successively from a single-atom cavity. In the schemes, coherent state of light is used instead of single photon source, homodyne measurement on coherent light is done kastead of single photon detection, and no need for individually addressing keeps the schemes easy to implement from the experimental point of view. The successful probabilities of our protocols approach unity in the ideal case.
基金Project supported by the National Natural Science Foundation of China (Grant No 10574022)Natural Science Foundation of Fujian Province of China (Grant Nos 2007J0002 and 2006J0230)Foundation for Universities in Fujian Province (Grant No 2007F5041)
文摘This paper presents a direct implementation scheme of the non-local multi-qubit controlled phase gate by using optical fibres and adiabatic passage. The smaller operation number for implementing the multi-qubit controlled phase gate and needlessness for addressing individually save physical resource and lower the difficulties of experiment. Mean- while, the scheme is immune from some decoherence effects such as the atomic spontaneous emission and fibre loss. In principle, it is scalable.
基金Supported by the National Natural Science Foundation of China under Grant No 10574022, the Natural Science Foundation of Fujian Province under Grant Nos 2006J0230 and A0410016, and the Funds of Education Committee of Fujian Province under Grant No JB05334.
文摘We propose a scheme for preparing multiple-photon GHZ state via cavity-assisted interaction. There are n-pair single-photon pulses successively injected and reflected from two sides of the cavity, which traps one atom. After the atomic state is measured, a 2n-photon GHZ state is produced. In the ideal case, the successful probability of the scheme is close to unity.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11674094,11774089,11874146,11981260012,and 12034007)the Shanghai Natural Science Foundation,China(Grant Nos.18ZR1410500 and 18DZ2252400).
文摘We present a scheme for the quantum storage of single photons using electromagnetically induced transparency(EIT)in a low-finesse optical cavity,assisted by state-selected spontaneous atomic emission.Mediated by the dark mode of cavity EIT,the destructive quantum interference between the cavity input-output channel and state-selected atomic spontaneous emission leads to strong absorption of single photons with unknown arrival time and pulse shapes.We discuss the application of this phenomenon to photon counting using stored light.
基金supported by the China Post-Doctoral Science Foundation (Nos. 2011M500739 and 2011M500068)the Fundamental Research Funds for the Central Universities (No. WM1214019)the National Natural Science Foundation of China (Nos. 11274112, 11204080, and 11074263)
文摘Global change in the dispersive behavior of terahertz (THz) plasmons on metal wires with wide radii ranging from 5 nm to 0.5 mm is systematically investigated. Through rigorous numerical calculations, we find that the dispersion of a metal wire with a radius of 5 nm increases by about 4-6 orders of magnitude compared with the case of a metallic wire with a radius of 0.5 mm. Zero-dispersion points appear when the frequency is lower than 3 THz, and the positions of the zero-dispersion points can shift with the frequency. Finally, we provide an explicit expression that agrees verv well with the numerical calculations.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11674094,11474092,and 11774089)
文摘We analyze the transport property of a single photon in a one-dimensional coupled resonator waveguide coupled with a Λ-type emitter assisted by an additional cavity. The reflection and transmission coefficients of the inserted photon are obtained by the stationary theory. It is shown that the polarization state of the inserted photon can be converted with high efficiency. This study may inspire single-photon devices for scalable quantum memory.