In this study,we design a refractive index(RI)sensor using a novel cadmium telluride photonic crystal fiber(TPCF).Based on four-wave mixing(FWM),the changes in RI can be accurately detected,and RI sensing in the mid-i...In this study,we design a refractive index(RI)sensor using a novel cadmium telluride photonic crystal fiber(TPCF).Based on four-wave mixing(FWM),the changes in RI can be accurately detected,and RI sensing in the mid-infrared region(MIR)can be achieved by detecting wavelength shifts in the Stokes and anti-Stokes spectra caused by the changes in RI of the liquid to be measured.When the pump wavelength of FWM lies in the normal and abnormal dispersion regions of the TPCF,the RI response of the idler frequency wave and the signal wave are analyzed by numerical simulation methods.The simulation results show that the RI sensitivity of the sensor can be as high as 7692 nm/RIU with a linearity is up to 99.9%at the pump wavelength of 3380 nm.To our knowledge,the RI sensing sensitivity of the MIR is presented for the first time in this study by using FWM in the non-silicon PCF.展开更多
The effect of doping concentrations and a transverse external magnetostatic field on operational characteristics of parametric amplification of backward Stokes signal has been studied, using hydrodynamic model of semi...The effect of doping concentrations and a transverse external magnetostatic field on operational characteristics of parametric amplification of backward Stokes signal has been studied, using hydrodynamic model of semiconductors, in the far infrared regime. The model suggests three achievable resonance conditions: (i) lattice frequency and plasma frequency (ii) stokes frequency and electron-cyclotron frequency (iii) stokes frequency and hybrid (plasma and electron-cyclotron) frequency and these conditions have been utilised, on one hand, to substantially reduce the value of threshold intensity for onset of the parametric amplification and on the other hand, for switching of parametric large positive and negative gain coefficient (i.e. amplification and absorption). For example a strong transverse magnetostatic field 10.0 T with free carrier concentration 1.5 x 1019m-3 enhances the gain by a factor of 103 as in its absence. Results also suggest that a weakly piezoelectric III–V semiconductor duly illuminated by slightly off-resonant not-too-high-power pulsed lasers with pulse duration sufficiently larger than the acoustic phonon lifetime is one of promising hosts for parametric amplifier/frequency converter.展开更多
The theory model of fiber optical parametric amplifier (FOPA) was introduced, which is based on optical nonlinear effect. And then numerical simulation was done to analyze and discuss the gain spectral characteristics...The theory model of fiber optical parametric amplifier (FOPA) was introduced, which is based on optical nonlinear effect. And then numerical simulation was done to analyze and discuss the gain spectral characteristics of one-pump and two-pump FOPA. The results show that for one-pump FOPA, when pump wavelength is near to fiber zero-dispersion wavelength(ZDW), the gain flatness is better, and with the increase of the pump power, fiber length and its nonlinear coefficient, the gain value will increase while the gain bandwidth will become narrow. For two-pump FOPA, when the pump central wavelength is near to fiber ZDW, the gain flatness is better. Moreover, by decreasing the space of two pumps wavelength, the gain flatness can be improved. Finally, some problems existing in FOPA were addressed.展开更多
We report an observation of the second-order correlation between twin beams generated by amplified spontaneous parametric down-conversion operating above threshold with kilowatt-level peak power, from a periodically p...We report an observation of the second-order correlation between twin beams generated by amplified spontaneous parametric down-conversion operating above threshold with kilowatt-level peak power, from a periodically poled Li Ta O3 crystal via a single-pass scheme. Photocurrent correlation was measured because of the bright photon streams, with raw visibility of 37.9% or 97.3% after electronic filtering. As expected in our theory, this correlation is robust and insensitive to parametric gain and detection loss, enabling important applications in optical communications, precision measurement, and nonlocal imaging.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant No.61775032)the National Key Research and Development Program of China(Grant No.2017YFA0701200)+4 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.N2104022 and N2004021)the China Postdoctoral Science Foundation(Grant No.2021M690563)the Natural Science Foundation of Science and Technology Department of Liaoning Province(Grant No.2020-BS-046)the Hebei Natural Science Foundation(Grant No.F2020501040)the 111 Project(Grant No.B16009).
文摘In this study,we design a refractive index(RI)sensor using a novel cadmium telluride photonic crystal fiber(TPCF).Based on four-wave mixing(FWM),the changes in RI can be accurately detected,and RI sensing in the mid-infrared region(MIR)can be achieved by detecting wavelength shifts in the Stokes and anti-Stokes spectra caused by the changes in RI of the liquid to be measured.When the pump wavelength of FWM lies in the normal and abnormal dispersion regions of the TPCF,the RI response of the idler frequency wave and the signal wave are analyzed by numerical simulation methods.The simulation results show that the RI sensitivity of the sensor can be as high as 7692 nm/RIU with a linearity is up to 99.9%at the pump wavelength of 3380 nm.To our knowledge,the RI sensing sensitivity of the MIR is presented for the first time in this study by using FWM in the non-silicon PCF.
文摘The effect of doping concentrations and a transverse external magnetostatic field on operational characteristics of parametric amplification of backward Stokes signal has been studied, using hydrodynamic model of semiconductors, in the far infrared regime. The model suggests three achievable resonance conditions: (i) lattice frequency and plasma frequency (ii) stokes frequency and electron-cyclotron frequency (iii) stokes frequency and hybrid (plasma and electron-cyclotron) frequency and these conditions have been utilised, on one hand, to substantially reduce the value of threshold intensity for onset of the parametric amplification and on the other hand, for switching of parametric large positive and negative gain coefficient (i.e. amplification and absorption). For example a strong transverse magnetostatic field 10.0 T with free carrier concentration 1.5 x 1019m-3 enhances the gain by a factor of 103 as in its absence. Results also suggest that a weakly piezoelectric III–V semiconductor duly illuminated by slightly off-resonant not-too-high-power pulsed lasers with pulse duration sufficiently larger than the acoustic phonon lifetime is one of promising hosts for parametric amplifier/frequency converter.
文摘The theory model of fiber optical parametric amplifier (FOPA) was introduced, which is based on optical nonlinear effect. And then numerical simulation was done to analyze and discuss the gain spectral characteristics of one-pump and two-pump FOPA. The results show that for one-pump FOPA, when pump wavelength is near to fiber zero-dispersion wavelength(ZDW), the gain flatness is better, and with the increase of the pump power, fiber length and its nonlinear coefficient, the gain value will increase while the gain bandwidth will become narrow. For two-pump FOPA, when the pump central wavelength is near to fiber ZDW, the gain flatness is better. Moreover, by decreasing the space of two pumps wavelength, the gain flatness can be improved. Finally, some problems existing in FOPA were addressed.
基金the National Key R&D Program of China(Nos.2019YFA0705000 and 2017YFA0303700)the National Natural Science Foundation of China(Nos.51890861,11690031,11627810,11674169,and 11974178).
文摘We report an observation of the second-order correlation between twin beams generated by amplified spontaneous parametric down-conversion operating above threshold with kilowatt-level peak power, from a periodically poled Li Ta O3 crystal via a single-pass scheme. Photocurrent correlation was measured because of the bright photon streams, with raw visibility of 37.9% or 97.3% after electronic filtering. As expected in our theory, this correlation is robust and insensitive to parametric gain and detection loss, enabling important applications in optical communications, precision measurement, and nonlocal imaging.
