We study the dynamics of the entropy correlations and entanglement in a system of interaction of a superconducting charge qubit with a single-mode resonant cavity subject to noise considered as two-state random phase ...We study the dynamics of the entropy correlations and entanglement in a system of interaction of a superconducting charge qubit with a single-mode resonant cavity subject to noise considered as two-state random phase telegraph noise. We show that although the noise has an apparent suppressing effect on the evolution of the entropies of the qubit and the field and also on the entanglement in the system, the entropy exchange between the qubit and the field is independent of it during the time evolution of the system.展开更多
In this paper, we consider a system consisting of two capacitively coupled superconducting islands viaJosephson junctions. We show that it can be reduced to two coupling harmonic oscillators under certain conditions,a...In this paper, we consider a system consisting of two capacitively coupled superconducting islands viaJosephson junctions. We show that it can be reduced to two coupling harmonic oscillators under certain conditions,and can be solved exactly in terms of a displacing transformation, a beam-splitter-like transformation, and a squeezingtransformation. It is found that the system evolves by a rotated-squeezed-coherent state when the system is initially in acoherent state. Quantum dynamics of the Cooper pairs in the two superconducting islands are investigated. It is shownthat the number of the Cooper pairs in the two islands evolves periodically.展开更多
In the face of deteriorating environmental conditions in the world,water quality control is an urgent task.It can be solved by creating sensors with high accuracy and low cost,which requires the development of fundame...In the face of deteriorating environmental conditions in the world,water quality control is an urgent task.It can be solved by creating sensors with high accuracy and low cost,which requires the development of fundamentally new radiophysical methods that take advantage of the optical,microwave and millimeter wavelengths that have a significantly greater sensitivity to low concentrations of pollutants and a lower inertia.The article presents prototypes of measuring cells of the microwave and optical ranges as well as the results of an experimental study of water of various degrees of pollution with their help.The results show that the use of the highly sensitive method of capillary-waveguide resonance makes it possible to detect the presence of micro impurities in water with concentrations up to0.1%and to identify water even from sources of various natural origins.In addition,the use of measurements at several frequencies in the optical range will make it possible to solve the problem of creating water control sensors with high sensitivity to pollution and low cost.It can be concluded that the possibility of complex use of multiwave sensors(optical,infrared and microwave ranges)allows to increase the sensitivity and reliability of water quality assessment.展开更多
We report Raman lasing and the optical analog of electromagnetically-induced-transparency(EIT) in a whispering-gallery-mode(WGM) microtoroid resonator embedded in a low refractive index polymer matrix together with a ...We report Raman lasing and the optical analog of electromagnetically-induced-transparency(EIT) in a whispering-gallery-mode(WGM) microtoroid resonator embedded in a low refractive index polymer matrix together with a tapered fiber coupler. The microtoroid resonator supports both single mode and multimode Raman lasing with low power thresholds. Observations of Fano and EIT-like phenomena in a packaged microresonator will enable high resolution sensors and can be used in networks where slow-light effect is needed. These results will open up new possibilities for portable, robust, and stable WGM microlasers and resonator-based sensors for applications in various environments.展开更多
Transmission spectroscopy of two Nb double superconducting split-ring samples with different thicknesses on MgO substrates was measured by a continuous Tera-Hertz spectrometer.The transmission curves of two different ...Transmission spectroscopy of two Nb double superconducting split-ring samples with different thicknesses on MgO substrates was measured by a continuous Tera-Hertz spectrometer.The transmission curves of two different samples with the thicknesses of 50 and 150 nm at 7.5 K show dips at 480,545 GHz,respectively,which origin from the different capacities and inductances of the samples.For the sample of 50 nm,the dip shifts to lower frequency,also decreases in depth and increases in width with temperature or field increasing below T c of Nb film,while the sample of 150 nm does not show such a phenomenon.This thickness-dependent transmission behavior is due to the kinetic inductance and conductivity change of superfluid electrons in Nb film and may suggest a practical tunable THz filter based on the thinner samples.展开更多
The photon transport properties in one-dimensional coupled-resonator waveguide embedded with a quantum dot molecule are investigated. The calculations reveal that one can control the photon transport by using a gate e...The photon transport properties in one-dimensional coupled-resonator waveguide embedded with a quantum dot molecule are investigated. The calculations reveal that one can control the photon transport by using a gate electric field. The phase shift and group velocity delay of the transmitted single photon are discussed. This research may be found applications in integrated optoelectronic devices and solid quantum devices.展开更多
文摘We study the dynamics of the entropy correlations and entanglement in a system of interaction of a superconducting charge qubit with a single-mode resonant cavity subject to noise considered as two-state random phase telegraph noise. We show that although the noise has an apparent suppressing effect on the evolution of the entropies of the qubit and the field and also on the entanglement in the system, the entropy exchange between the qubit and the field is independent of it during the time evolution of the system.
文摘In this paper, we consider a system consisting of two capacitively coupled superconducting islands viaJosephson junctions. We show that it can be reduced to two coupling harmonic oscillators under certain conditions,and can be solved exactly in terms of a displacing transformation, a beam-splitter-like transformation, and a squeezingtransformation. It is found that the system evolves by a rotated-squeezed-coherent state when the system is initially in acoherent state. Quantum dynamics of the Cooper pairs in the two superconducting islands are investigated. It is shownthat the number of the Cooper pairs in the two islands evolves periodically.
文摘In the face of deteriorating environmental conditions in the world,water quality control is an urgent task.It can be solved by creating sensors with high accuracy and low cost,which requires the development of fundamentally new radiophysical methods that take advantage of the optical,microwave and millimeter wavelengths that have a significantly greater sensitivity to low concentrations of pollutants and a lower inertia.The article presents prototypes of measuring cells of the microwave and optical ranges as well as the results of an experimental study of water of various degrees of pollution with their help.The results show that the use of the highly sensitive method of capillary-waveguide resonance makes it possible to detect the presence of micro impurities in water with concentrations up to0.1%and to identify water even from sources of various natural origins.In addition,the use of measurements at several frequencies in the optical range will make it possible to solve the problem of creating water control sensors with high sensitivity to pollution and low cost.It can be concluded that the possibility of complex use of multiwave sensors(optical,infrared and microwave ranges)allows to increase the sensitivity and reliability of water quality assessment.
基金supported by the US Army Research Office(ARO)(W911NF-12-1-0026 and W911NF1710189)
文摘We report Raman lasing and the optical analog of electromagnetically-induced-transparency(EIT) in a whispering-gallery-mode(WGM) microtoroid resonator embedded in a low refractive index polymer matrix together with a tapered fiber coupler. The microtoroid resonator supports both single mode and multimode Raman lasing with low power thresholds. Observations of Fano and EIT-like phenomena in a packaged microresonator will enable high resolution sensors and can be used in networks where slow-light effect is needed. These results will open up new possibilities for portable, robust, and stable WGM microlasers and resonator-based sensors for applications in various environments.
基金supported by the Science Foundation of the Chinese Academy of Sciences (Grant No.KJCX2-SW-W20)the National Basic Research Program of China (Grant No.2011CB921702)
文摘Transmission spectroscopy of two Nb double superconducting split-ring samples with different thicknesses on MgO substrates was measured by a continuous Tera-Hertz spectrometer.The transmission curves of two different samples with the thicknesses of 50 and 150 nm at 7.5 K show dips at 480,545 GHz,respectively,which origin from the different capacities and inductances of the samples.For the sample of 50 nm,the dip shifts to lower frequency,also decreases in depth and increases in width with temperature or field increasing below T c of Nb film,while the sample of 150 nm does not show such a phenomenon.This thickness-dependent transmission behavior is due to the kinetic inductance and conductivity change of superfluid electrons in Nb film and may suggest a practical tunable THz filter based on the thinner samples.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 11004001 and 11105001the Key Project of Chinese Ministry of Education under Grant No. 212076the Anhui Provincial Natural Science Foundation under Grant No. 1208085QA09
文摘The photon transport properties in one-dimensional coupled-resonator waveguide embedded with a quantum dot molecule are investigated. The calculations reveal that one can control the photon transport by using a gate electric field. The phase shift and group velocity delay of the transmitted single photon are discussed. This research may be found applications in integrated optoelectronic devices and solid quantum devices.
