We make a rigorous exploration of the profiles of a few diagonal and off-diagonal components of linear (αxx, αyy, αxy andαyx), first nonlinear (βxxx, βyyy, βxyy andβyxx), and second nonlinear (γxxxx, γyyyy, ...We make a rigorous exploration of the profiles of a few diagonal and off-diagonal components of linear (αxx, αyy, αxy andαyx), first nonlinear (βxxx, βyyy, βxyy andβyxx), and second nonlinear (γxxxx, γyyyy, γxxyyandγyyxx) polarizabilities of quantum dots under the influence of external pulsed field. Simultaneous presence of additive white noise has also been considered. The quantum dot contains dopant described by a Gaussian potential. The numbers of pulse and the dopant location have been found to fabricate the said profiles jointly. The β components display greater complexity in their profiles in comparison with the α and γ counterparts. The presence of noise prominently enhances the influence of dopant coordinate on the polarizability profiles, particularly for α and γ components. However, for β components, the said influence becomes quite evident both in the presence and absence of additive noise. The study reveals some means of achieving stable, enhanced, and often maximized output of noise-driven linear and nonlinear polarizabilities.展开更多
Coherent radiation with frequencies ranging from 0.3 to 30 THz has recently become accessible using femtosecond laser technology.These terahertz(THz)waves have already been applied in spectroscopy and imaging and can ...Coherent radiation with frequencies ranging from 0.3 to 30 THz has recently become accessible using femtosecond laser technology.These terahertz(THz)waves have already been applied in spectroscopy and imaging and can be manipulated using static optical elements such as lenses,polarizers and filters.However,ultrafast modulation of THz radiation is required as well,for instance,in short-range wireless communication or for preparing shaped THz transients for the coherent control of numerous material excitations.Here,we demonstrate an all-optically created transient metamaterial that allows us to manipulate the polarization of THz waveforms with subcycle switch-on times.The polarization-modulated pulses are potentially interesting for controlling elementary motions such as the vibration of crystal lattices,the rotation of molecules and the precession of spins.展开更多
文摘We make a rigorous exploration of the profiles of a few diagonal and off-diagonal components of linear (αxx, αyy, αxy andαyx), first nonlinear (βxxx, βyyy, βxyy andβyxx), and second nonlinear (γxxxx, γyyyy, γxxyyandγyyxx) polarizabilities of quantum dots under the influence of external pulsed field. Simultaneous presence of additive white noise has also been considered. The quantum dot contains dopant described by a Gaussian potential. The numbers of pulse and the dopant location have been found to fabricate the said profiles jointly. The β components display greater complexity in their profiles in comparison with the α and γ counterparts. The presence of noise prominently enhances the influence of dopant coordinate on the polarizability profiles, particularly for α and γ components. However, for β components, the said influence becomes quite evident both in the presence and absence of additive noise. The study reveals some means of achieving stable, enhanced, and often maximized output of noise-driven linear and nonlinear polarizabilities.
基金We would like to thank the German Research Foundation for funding this work through Grant No.KA 3305/2-1.
文摘Coherent radiation with frequencies ranging from 0.3 to 30 THz has recently become accessible using femtosecond laser technology.These terahertz(THz)waves have already been applied in spectroscopy and imaging and can be manipulated using static optical elements such as lenses,polarizers and filters.However,ultrafast modulation of THz radiation is required as well,for instance,in short-range wireless communication or for preparing shaped THz transients for the coherent control of numerous material excitations.Here,we demonstrate an all-optically created transient metamaterial that allows us to manipulate the polarization of THz waveforms with subcycle switch-on times.The polarization-modulated pulses are potentially interesting for controlling elementary motions such as the vibration of crystal lattices,the rotation of molecules and the precession of spins.