We study the possible topological phase in a one-dimensional（1D） quantum wire with an oscillating Rashba spin–orbital coupling in real space. It is shown that there are a pair of particle–hole symmetric gaps formi...We study the possible topological phase in a one-dimensional（1D） quantum wire with an oscillating Rashba spin–orbital coupling in real space. It is shown that there are a pair of particle–hole symmetric gaps forming in the bulk energy band and fractional boundary states residing in the gap when the system has an inversion symmetry. These states are topologically nontrivial and can be characterized by a quantized Berry phase ±π or nonzero Chern number through dimensional extension. When the Rashba spin–orbital coupling varies slowly with time, the system can pump out 2 charges in a pumping cycle because of the spin flip effect. This quantized pumping is protected by topology and is robust against moderate disorders as long as the disorder strength does not exceed the opened energy gap.展开更多
In this paper,a phase-quantization all-optical analog-to-digital converter(ADC)scheme is proposed and experimentally demonstrated using a thin-film lithium niobate(TFLN)Mach–Zehnder modulator(MZM)and a star coupler,o...In this paper,a phase-quantization all-optical analog-to-digital converter(ADC)scheme is proposed and experimentally demonstrated using a thin-film lithium niobate(TFLN)Mach–Zehnder modulator(MZM)and a star coupler,overcoming the limitations of traditional phase-shift quantization approaches where increasing output ports leads to significantly higher design complexity.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.115074045 and 11204187)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20131284)
文摘We study the possible topological phase in a one-dimensional（1D） quantum wire with an oscillating Rashba spin–orbital coupling in real space. It is shown that there are a pair of particle–hole symmetric gaps forming in the bulk energy band and fractional boundary states residing in the gap when the system has an inversion symmetry. These states are topologically nontrivial and can be characterized by a quantized Berry phase ±π or nonzero Chern number through dimensional extension. When the Rashba spin–orbital coupling varies slowly with time, the system can pump out 2 charges in a pumping cycle because of the spin flip effect. This quantized pumping is protected by topology and is robust against moderate disorders as long as the disorder strength does not exceed the opened energy gap.
基金National Natural Science Foundation of China(62435016,62305291)。
文摘In this paper,a phase-quantization all-optical analog-to-digital converter(ADC)scheme is proposed and experimentally demonstrated using a thin-film lithium niobate(TFLN)Mach–Zehnder modulator(MZM)and a star coupler,overcoming the limitations of traditional phase-shift quantization approaches where increasing output ports leads to significantly higher design complexity.
