Strategy of state transfer for open quantum systems by no-knowledge feedback control: Via reverse engineering

It has long been interest to control the transfer of population between specified quantum states and protect the coherence of the system at the same time. In this paper, we investigate a scheme to improve the strategy of state transfer for open quantum systems using no-knowledge measurement-based feedback control and reverse engineering. In order to ensure that the system can process information effectively, we first design the control pulse in advance from the perspective of population and coherence and then verify it through numerical simulations. The research results show that, based on the designed control pulse, we can indeed drive the system from any initial state to the desired target state, and the coherence of the system can be effectively protected during the state transition.

Optimization control actions on electropneumatic valve of actuator of clutch control

Electropneumatic valves are a key element of the electropneumatic clutch control system for vehicles of categories N3 and M3. The speed and accuracy of the clutch control system depend on their parameters. When the operating conditions of the solenoid valve change, its initial parameters also change, even before the loss of serviceability. Goal. The goal of the work is to form dependencies that determine the parameters of the control signal for the clutch control system of vehicles of categories M3 and N3 in the conditions of change of supply voltage, pressure drop on the valve and ambient temperature. Methodology. To achieve this goal, an advanced mathematical model and onedimensional optimization method were used to determine the optimal control effect on the electropneumatic valve of the clutch control system. Results. The block diagram of the control pulse in different modes of operation of the electropneumatic clutch control system is given. Based on the calculated data, the characteristic areas of operation of the electropneumatic valve are determined and the purpose for the optimization process is determined. Based on the defined range of data change and the accuracy of finding the optimal value, a rational optimization method is determined. By modeling the operation of the solenoid valve with parameters according to the chosen optimization method, the response surfaces were constructed relative to the control pulse depending on such parameters as supply voltage of the vehicle onboard network, ambient temperature and pressure drop on the solenoid valve. Originality. The error in the reproduction of the theoretical response surfaces based on the parameters of the clutch and the electronic control unit is also determined. Theoretical aspects for providing the required inductance of the solenoid valve coil are shown. Practical value. A method for determining the pressure drop on an electropneumatic valve is proposed. The method takes into account the change in pressure during operation of the clutch control system due to wear of the friction plate. The error in ensuring the duration of the control pulse due to the presence of hysteresis in the operation of the clutch and the executive control device is estimated.

Implementasi Hysterisis Current Control Pulse Witdh Modulation (HCCPWM) Untuk Inverter 3 Fasa

Based on the source used, there are several types of converters, one of which is a voltage source converter (VSC). In this study, using a converter that can work as an inverter. In industry, an inverter is useful for supplying the AC voltage source from industrial plants with DC sources, by varying the voltage and output frequency of the inverter. The method used is the HCCPWM generation method or Hysterisis Current Control Pulse Witdh Modulation. This method was chosen because it has several advantages which are good stability, very fast transient response and good accuracy. To activate HCCPWM, a 3 phase reference current signal is first made in the Matlab Simulink, this reference current is then compared with the actual current from the current sensor, then the error is controlled with the hysteresis band. In Arduino mega2560, the pulses generated by HCCPWM in the Matlab Simulink are converted into a duty cycle. The modulated pulse generated by the Arduino PWM pin will be increased using a gate drive circuit, so that the voltage is obtained according to the voltage required by the Mosfet to activate the switch. The results of the tests that have been done show that the voltage source converter (VSC) designed in this study has worked well as intended. This can be seen from the actual current from the current sensor which has been compared with the reference voltage using the HCCPWM method which is included in the Simulink Matlab program.

Design and Analysis of X-OR Gate and 4-Bit Binary to 4-Bit Gray and Gray to Binary Code Converter Using Dual Control Dual SOA TOAD (DCDS-TOAD)

Background: In this paper we have design and analyzed 4-bit binary to 4-bit gray code and 4-bit gray to 4-bit gray code converter using dual control dual semiconductor optical amplifier terahertz optical asymmetric demultiplexer (DCDS-TOAD). We used control pulse as a Soliton pulse train. We calculate the extinction ratio, contrast ratio and Q value and found very high values. The high values of E.R., C.R. and Q value distinguishes the high (‘1’) level to the low(‘0’) very clearly also shown the variation of E.R., C.R. and Q value with control pulse energy and amplified spontaneous emission power factor. Methods: The basic equations governing the TOAD performance is simulated using MATLAB. The extinction ratio, contrast ratio and Q value are calculated for analysis of the device. Results: Results of operation for the code converters are performed at a bit rate of 100Gbps. The structure of DCDSTOAD enable us to achieve high values of ER(~ 81dB), CR(~83dB) and Q factor (86dB). A high Q factor shows very low bit error rate (BER). The eye diagram shows a large eye opening (REOP~98.5%). Conclusion: Design and analyzed 4-bit binary to 4-bit gray code and 4-bit gray to 4-bit gray code converter using dual control dual semiconductor optical amplifier terahertz optical asymmetric demultiplexer (DCDS-TOAD) is proposed and analyzed. We used control pulse as a Soliton pulse train. The proposed X-OR gate finds applications in many devices.

Ultrafast control of fractional orbital angular momentum of microlaser emissions

On-chip integrated laser sources of structured light carrying fractional orbital angular momentum (FOAM) are highly desirable for the forefront development of optical communication and quantum information–processing technologies. While integrated vortex beam generators have been previously demonstrated in different optical settings, ultrafast control and sweep of FOAM light with low-power control, suitable for high-speed optical communication and computing, remains challenging. Here we demonstrate fast control of the FOAM from a vortex semiconductor microlaser based on fast transient mixing of integer laser vorticities induced by a control pulse. A continuous FOAM sweep between charge 0 and charge +2 is demonstrated in a 100 ps time window, with the ultimate speed limit being established by the carrier recombination time in the gain medium. Our results provide a new route to generating vortex microlasers carrying FOAM that are switchable at GHz frequencies by an ultrafast control pulse.

Ultraviolet All-Optical Switching via Zinc Oxide Thin Films

Zinc oxide (ZnO) is a semiconductor material exhibiting a wide bandgap in the ultraviolet (UV) region. ZnO is a promising material for use in short-wave optoelectronic devices such as all-optical switches (AOSs). Our switch is composed of a polycrystalline ZnO thin film grown by DC sputter deposition and uses a 120ps control pulse tuned to the band edge of the film to modify the transmission of a weaker signal pulse. The signal light is heavily absorbed in the absence of the control pulse, representing an off state of the switch. The control pulse, when incident on the film, resonantly excites electrons to create excitons. This decreases the material’s absorption by filling energy states and screening the built-in electric field of the ZnO. Consequently, more signal light is transmitted by the film, representing an on state.