We propose a scheme in which an arbitrary incidence can be made perfectly reflected/transmitted if a phase setup is adjusted under a specific condition. We analyze the intracavity field variation as well as the output field with changing closed-loop phase of atomic system and relative phase of input probe beams. And we obtain the condition for perfect transmitter or reflector. By adjusting two phase setups, the medium absorption and light interference can be controlled so that photon escape from cavity can be modulated, thus the intensity switching based on phase control can be realized. Then based on the transmission/reflection analysis, total absorption of this system can be investigated. Therefore our scheme can be used as an absorption interferometer to explore the optical absorption in some complicated system. The phase delay dependent on phi_1 or phi_2 in output light intensity can be applied in the realization of quantum phase gate and subtle wave filter. And based on this scheme, we implement the state transfer between perfect transmitter/reflector and non-perfect coherent photon absorber via relative-phase modulation.
We propose a scheme in which an arbitrary incidence can be made perfectly reflected/transmitted if a phase setup is adjusted under a specific condition. We analyze the intracavity field variation as well as the output field with changing closed-loop phase of atomic system and relative phase of input probe beams. And we obtain the condition for perfect transmitter or reflector. By adjusting two phase setups, the medium absorption and light interference can be controlled so that photon escape from cavity can be modulated, thus the intensity switching based on phase control can be realized. Then based on the transmission/reflection analysis, total absorption of this system can be investigated. Therefore our scheme can be used as an absorption interferometer to explore the optical absorption in some complicated system. The phase delay dependent on phi_1 or phi_2 in output light intensity can be applied in the realization of quantum phase gate and subtle wave filter. And based on this scheme, we implement the state transfer between perfect transmitter/reflector and non-perfect coherent photon absorber via relative-phase modulation.
We propose a scheme in which an arbitrary incidence can be made perfectly reflected/transmitted with a phase modulator. We analyze the variation of intracavity field as well as output field with closed-loop phase ϕ 1 of the control fields and relative phase ϕ 2 of the probe beams. With two phases, medium absorption and light interference can be controlled so that photon escape from the cavity can be manipulated, thus an intensity switching based on phase modulation can be realized. And the condition for perfect transmitter or reflector is obtained. Then based on the transmission/reflection analysis, the total absorption of this system can be investigated. Therefore our scheme can be used as an absorption interferometer to explore the optical absorption in some complicated system. The state delay of the output light intensity, which is dependent on ϕ 1 or ϕ 2, can be applied in the realization of quantum phase gate and subtle wave filter. And based on this scheme, we implement the state transfer between perfect transmitter/reflector and non-perfect coherent photon absorber via relative-phase modulation.
We propose and analyze a scheme for controlling coherent photon transmission and reflection in a cavity-quantum-electrodynamics (CQED) system consisting of an optical resonator coupled with three-level atoms coherently prepared by a control laser from free space. When the control laser is off and the cavity is excited by two identical light fields from two ends of the cavity, the two input light fields can be completely absorbed by the CQED system and the light energy is converted into the excitation of the polariton states, but no light can escape from the cavity. Two distinct cases of controlling the perfect photon absorption are analyzed: (a) when the control laser is tuned to the atomic resonance and creates electromagnetically induced transparency, the perfect photon absorption is suppressed and the input light fields are nearly completely transmitted through the cavity; (b) when the control laser is tuned to the polariton state resonance and inhibits the polariton state excitation, the perfect photon absorption is again suppressed and the input light fields are nearly completely reflected from the cavity. Thus, the CQED system can act as a perfect absorber or near-perfect transmitter and/or reflector by simply turning the control laser off or on. Such interference control of the coherent photon-atom interaction in the CQED system should be useful for a variety of applications in optical logical devices.
We propose a scheme for controlling coherent photon absorption by electromagnetically induced transparency (EIT) in a three-level atom-cavity system. Coherent perfect absorption (CPA) occurs when time-reversed symmetry of lasing process is obtained with the destructive interference at the cavity interfaces. The frequency range of CPA is generally dependent on the decay rates of the cavity mirrors. The smaller decay rate of the cavity mirror causes the wider frequency range of CPA, and the needed intensity of the probe fields is larger to satisfy CPA condition for a given frequency. Although Rabi frequency of the control laser has little effect on the frequency range of CPA, with EIT-type quantum interference, the CPA mode is tunable by the control laser. In addition, with the relative phase, the probe fields can be perfectly transmitted and/or reflected. Therefore, the system can be used as a controllable coherent perfect absorber or transmitter (reflector), and our work may have practical applications in optical logic devices.
With the rapid development of nano-physics and quantum optics, optico-mechanical coupling system is developing toward the miniaturization and lightweight. The physical characteristics of optical cavity and applications of optic-mechanical devices have received much attention. In this paper, a generalized three-mode cavity optico-mechanical system is presented, the steady-state responses of the system to the characteristics of weak detection of light absorption and dispersion in several different coherent driving modes are studied. Situated in the middle of system is a portable total reflection mechanical oscillator with a reflectance of 100%, and located on each side is a fixed optical cavity mirror with partial transmittance, Three-mode cavity optical mechanical system consists of fixed-mirror, removable-vibrator, fixed-mirror structure. in which the two optical cavities are coupled by coupling a stronger control field and weak probe light with the same mechanical oscillator. Analysis and numerical results show that under the mechanism with different parameters, due to nonlinear effect of pressure, in the three-mode cavity optical mechanical system, there appear some interesting quantum coherent phenomena such as coherent perfect absorption, coherent perfect transmission and coherent perfect synthesis. When coherent perfect absorption occurs, the mutual conversion between input signal power full-field energies and oscillator vibration of internal coherence can be realized, and the law of conservation of energy is satisfied. When relaxation rate due to mechanical oscillator is very small, the coherent perfect transmission is completely transmitted from the system side of the input field to the other side in the case of no loss of energy. And mechanical relaxation rate of the oscillator approaches to zero in the middle, which can ensure that the perfect transmission of the detection field takes place on one side, and the field total reflection and coherent perfect synthesis happen on the other side of. In addition, we alsofind that the adjustment of coupling between cavity and cavity can change the intensity of the probe field of quantum coherent control thereby realizing that the output of the detection field is transformed between coherent perfect absorption and coherence transmission; through simple phase modulation the output direction and input direction of detection field for left cavity-right cavity can swap mutually. So, these dynamic controls in quantum information networks can be used to construct some optical devices with special functions, such as photon switch, photo router, photon exchange machine, etc.
-type atomic system driven resonantly by three coherent fields in a closed-loop coupling configuration. Owing to phase-controlled quantum interference, the real part of the induced complex permittivity becomes negative with vanishing imaginary part over a finite range of probe detuning. As a consequence, the complex refractive index exhibits a vanishing real part at a specific spectral detuning. Under this condition, the reflectance of the probe beam entering the medium reaches unity with ultimate suppression of transmittance. This leads to the phenomenon of perfect optically induced reflection (OIR). The tunable nature of OIR provides a new route for manipulating light propagation. The present study holds promise for its applications in the field of photonics. To this aim, we have demonstrated a two-port all-optical switching application at low light levels.
A coherent perfect absorber is essentially a specially designed Fabry-Perot interferometer, which completely extinguishes the incident coherent light. The one- and two-beam coherent perfect absorbers have been analyzed using classical electrodynamics by considering index matching in layered structures to totally suppress reflections. This approach presents a clear and physically intuitive picture for the principle of operation of a perfect absorber. The results show that the incident beam(s) must have correct phases and amplitudes, and the real and imaginary parts of the refractive indices of the media in the interferometer must satisfy a well-defined relation. Our results are in agreement with those obtained using the S-matrix analysis. However, the results were obtained solely based on the superposition of waves from multiple reflections without invoking the concept of time reversal as does the S-matrix approach. Further analysis shows that the two-beam device can be configured to function as a phase-controlled three-state switch.