This work presents a brief review of our recent research on an antiresonant mechanism named core antiresonant reflection(CARR),which leads to a broadband terahertz(THz)spectrum output with periodic dips at resonant fr...This work presents a brief review of our recent research on an antiresonant mechanism named core antiresonant reflection(CARR),which leads to a broadband terahertz(THz)spectrum output with periodic dips at resonant frequencies after its transmission along a hollow-core tubular structure(e.g.,a paper tube).The CARR theory relies only on parameters of the tube core(e.g.,the inner diameter)rather than the cladding,thus being distinct from existing principles such as the traditional antiresonant reflection inside optical waveguides(ARROWs).We demonstrate that diverse tubular structures,including cylindrical,polyhedral,spiral,meshy,and notched hollow tubes with either transparent or opaque cladding materials,as well as a thick-walled hole,could indeed become CARR-type resonators.Based on this CARR effect,we also perform various applications,such as pressure sensing with paper-folded THz cavities,force/magnetism-driven chiral polarization modulations,and single-pulse measurements of the angular dispersion of THz beams.In future studies,the proposed CARR method promises to support breakthroughs in multiple fields by means of being extended to more kinds of tubular entities for enhancing their interactions with light waves in an antiresonance manner.展开更多
A fiber-optic sensor for the simultaneous measurement of strain and temperature is proposed and experimentally demonstrated based on Fabry–Pérot(FP) interference and the antiresonance(AR) mechanism. The sensor w...A fiber-optic sensor for the simultaneous measurement of strain and temperature is proposed and experimentally demonstrated based on Fabry–Pérot(FP) interference and the antiresonance(AR) mechanism. The sensor was implemented using a single-mode fiber(SMF)–hollow-core fiber–SMF structure. A temperature sensitivity of 21.11 pm/℃ was achieved by tracing the troughs of the envelope caused by the AR mechanism, and a strain sensitivity of 2 pm/με was achieved by detecting the fine fringes caused by the FP cavity. The results indicate that the dual-parameter sensor is stable and reliable.展开更多
The paper studies photon-associated transmission through a quantum wire with a side-coupled stub tuner, to which an external microwave field applies, in terms of the approach developed by Cai. The inelastic scattering...The paper studies photon-associated transmission through a quantum wire with a side-coupled stub tuner, to which an external microwave field applies, in terms of the approach developed by Cai. The inelastic scattering of an incoming electron and the photon field lead to photon-electronic transmission though quantum wire. It is found that single photon absorbing (emitting) of the incoming electron in the stub can bring about antiresonant transmission in the quantum wire. The influence of the feedback mechanism from inelastic scattering process on elastic channel transmission is also examined. Total transmission coefficient as a function of photon energy exhibits non-periodic oscillation peaks. With the increasing of photon-electron coupling constant, the amplitude of these oscillation peaks enhances. Key words stub tuner - photon-associated transport - antiresonance PASC 2001 N72.25 Dc - 73.40.Ty - 73.23. Ad展开更多
Using the tight-binding approximation and the transfer matrix method, this paper studies the electronic transport properties through a periodic array of quantum-dot （QD） rings threaded by a magnetic flux. It demonst...Using the tight-binding approximation and the transfer matrix method, this paper studies the electronic transport properties through a periodic array of quantum-dot （QD） rings threaded by a magnetic flux. It demonstrates that the even^odd parity of the QD number in a single ring and the number of the QD rings in the array play a crucial role in the electron transmission. For a single QD ring, the resonance and antiresonance transmission depend not only on the applied magnetic flux but also on the difference between the number of QDs on the two arms of the ring. For an array of QD rings, the transmission properties are related not only to the even-odd parity of the number No of QDs in the single ring but also to the even-odd parity of the ring number N in the array. When the incident electron energy is aligned with the site energy, for the array of N rings with No = odd the antiresonance transmission cannot occur but the resonance transmission may occur and the transmission spectrum has N resonance peaks （N - 1 resonance peaks） in a period for N = odd （for N = even）. For the array of N rings with No = even the transmission properties depend on the flux threading the ring and the QD number on one arm of the ring. These results may be helpful in designing QD devices.展开更多
By means of the transfer matrix technique, the electronic transport through a quantum waveguide in the presence of a magnetic obstacle is investigated theoretically. By comparing the calculated conductance spectra of ...By means of the transfer matrix technique, the electronic transport through a quantum waveguide in the presence of a magnetic obstacle is investigated theoretically. By comparing the calculated conductance spectra of the opposite spin electrons, we find that there exists a notable spin filtering window in the low energy region. Dependences of such a spin filtering window on the size, position and potential strength of the magnetic obstacle are studied in detail.展开更多
According to the one-dimensional antiresonance effect （Wang X R, Wang Y and Sun Z Z 2003 Phys. Rev. B 65 193402）, we propose a possible spin-polarized current generation device. Our proposed model consists of one ch...According to the one-dimensional antiresonance effect （Wang X R, Wang Y and Sun Z Z 2003 Phys. Rev. B 65 193402）, we propose a possible spin-polarized current generation device. Our proposed model consists of one chain and an impurity coupling to the chain. The energy level of the impurity can be occupied by an electron with a specific spin, and the electron with such a spin is blocked because of the antiresonance effect. Based on this phenomenon our model can generate the spin-polarized current flowing through the chain due to different polarization rates. On the other hand, the device can also be used to measure the generated spin accumulation. Our model is feasible with today＇s technology.展开更多
We theoretically study the transport properties in the T-shaped double-quantum-dot structure,by considering the dot in the main channel to be coupled to the Majorana bound state(MBS)at one end of the topological super...We theoretically study the transport properties in the T-shaped double-quantum-dot structure,by considering the dot in the main channel to be coupled to the Majorana bound state(MBS)at one end of the topological superconducting nanowire.It is found that the side-coupled dot governs the effect of the MBS on the transport behavior.When its level is consistent with the energy zero point,the MBS contributes little to the conductance spectrum.Otherwise,the linear conductance exhibits notable changes according to the inter-MBS coupling manners.In the absence of inter-MBS coupling,the linear conductance value keeps equal to e^(2)/2 h when the level of the side-coupled dot departs from the energy zero point.However,the linear conductance is always analogous to the MBS-absent case once the inter-MBS coupling comes into play.These findings provide new information about the leakage effect of MBSs in quantum-dot structures.展开更多
Based on an investigation of existing methods for estimating fre- quency response functions(FRF)at home and abroad,two methods are ad- vanced.The one,denoted as H_(12),avoids underestimates at resonances and overestim...Based on an investigation of existing methods for estimating fre- quency response functions(FRF)at home and abroad,two methods are ad- vanced.The one,denoted as H_(12),avoids underestimates at resonances and overestimates at antiresonances,while the other,denoted as H_F,regards the noise ratio of output to input as varying with the frequency.Finally,a soft- ware for estimating frequency response functions is introduced.A modal test for a steel plate excited with a random signal is made,and frequency response function estimates are made,making use of the above software.The test re- sults conform well with the theoretical analysis.展开更多
基金supported by the National Natural Science Foundation of China(Nos.61988102 and 62335012)the Youth Sci-Tech“Qimingxing”Program of Shanghai(No.22QC1400300)the National Key Research and Development Program of China(No.2022YFA1404004)。
文摘This work presents a brief review of our recent research on an antiresonant mechanism named core antiresonant reflection(CARR),which leads to a broadband terahertz(THz)spectrum output with periodic dips at resonant frequencies after its transmission along a hollow-core tubular structure(e.g.,a paper tube).The CARR theory relies only on parameters of the tube core(e.g.,the inner diameter)rather than the cladding,thus being distinct from existing principles such as the traditional antiresonant reflection inside optical waveguides(ARROWs).We demonstrate that diverse tubular structures,including cylindrical,polyhedral,spiral,meshy,and notched hollow tubes with either transparent or opaque cladding materials,as well as a thick-walled hole,could indeed become CARR-type resonators.Based on this CARR effect,we also perform various applications,such as pressure sensing with paper-folded THz cavities,force/magnetism-driven chiral polarization modulations,and single-pulse measurements of the angular dispersion of THz beams.In future studies,the proposed CARR method promises to support breakthroughs in multiple fields by means of being extended to more kinds of tubular entities for enhancing their interactions with light waves in an antiresonance manner.
基金financially supported in part by the National Natural Science Foundation of China (No. 61675055)the Shenzhen Municipal Science and Technology Plan Project (Nos. JCYJ20170815140136635 and JCYJ20190806143818818)。
文摘A fiber-optic sensor for the simultaneous measurement of strain and temperature is proposed and experimentally demonstrated based on Fabry–Pérot(FP) interference and the antiresonance(AR) mechanism. The sensor was implemented using a single-mode fiber(SMF)–hollow-core fiber–SMF structure. A temperature sensitivity of 21.11 pm/℃ was achieved by tracing the troughs of the envelope caused by the AR mechanism, and a strain sensitivity of 2 pm/με was achieved by detecting the fine fringes caused by the FP cavity. The results indicate that the dual-parameter sensor is stable and reliable.
文摘The paper studies photon-associated transmission through a quantum wire with a side-coupled stub tuner, to which an external microwave field applies, in terms of the approach developed by Cai. The inelastic scattering of an incoming electron and the photon field lead to photon-electronic transmission though quantum wire. It is found that single photon absorbing (emitting) of the incoming electron in the stub can bring about antiresonant transmission in the quantum wire. The influence of the feedback mechanism from inelastic scattering process on elastic channel transmission is also examined. Total transmission coefficient as a function of photon energy exhibits non-periodic oscillation peaks. With the increasing of photon-electron coupling constant, the amplitude of these oscillation peaks enhances. Key words stub tuner - photon-associated transport - antiresonance PASC 2001 N72.25 Dc - 73.40.Ty - 73.23. Ad
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10774094 and 10775091)National Fundamental Fund of Personnel Training (Grant No. J0730317)Natural Science Foundation of Shanxi Province of China (GrantNo. 2009011001-1)
文摘Using the tight-binding approximation and the transfer matrix method, this paper studies the electronic transport properties through a periodic array of quantum-dot （QD） rings threaded by a magnetic flux. It demonstrates that the even^odd parity of the QD number in a single ring and the number of the QD rings in the array play a crucial role in the electron transmission. For a single QD ring, the resonance and antiresonance transmission depend not only on the applied magnetic flux but also on the difference between the number of QDs on the two arms of the ring. For an array of QD rings, the transmission properties are related not only to the even-odd parity of the number No of QDs in the single ring but also to the even-odd parity of the ring number N in the array. When the incident electron energy is aligned with the site energy, for the array of N rings with No = odd the antiresonance transmission cannot occur but the resonance transmission may occur and the transmission spectrum has N resonance peaks （N - 1 resonance peaks） in a period for N = odd （for N = even）. For the array of N rings with No = even the transmission properties depend on the flux threading the ring and the QD number on one arm of the ring. These results may be helpful in designing QD devices.
文摘By means of the transfer matrix technique, the electronic transport through a quantum waveguide in the presence of a magnetic obstacle is investigated theoretically. By comparing the calculated conductance spectra of the opposite spin electrons, we find that there exists a notable spin filtering window in the low energy region. Dependences of such a spin filtering window on the size, position and potential strength of the magnetic obstacle are studied in detail.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10904082 and 10875072)
文摘According to the one-dimensional antiresonance effect （Wang X R, Wang Y and Sun Z Z 2003 Phys. Rev. B 65 193402）, we propose a possible spin-polarized current generation device. Our proposed model consists of one chain and an impurity coupling to the chain. The energy level of the impurity can be occupied by an electron with a specific spin, and the electron with such a spin is blocked because of the antiresonance effect. Based on this phenomenon our model can generate the spin-polarized current flowing through the chain due to different polarization rates. On the other hand, the device can also be used to measure the generated spin accumulation. Our model is feasible with today＇s technology.
基金the Liao Ning Revitalization Talents Program(Grant No.XLYC1907033)the Fundamental Research Funds for the Central Universities,China(Grant No.N2002005)the National Natural Science Foundation of China(Grant No.11905027)。
文摘We theoretically study the transport properties in the T-shaped double-quantum-dot structure,by considering the dot in the main channel to be coupled to the Majorana bound state(MBS)at one end of the topological superconducting nanowire.It is found that the side-coupled dot governs the effect of the MBS on the transport behavior.When its level is consistent with the energy zero point,the MBS contributes little to the conductance spectrum.Otherwise,the linear conductance exhibits notable changes according to the inter-MBS coupling manners.In the absence of inter-MBS coupling,the linear conductance value keeps equal to e^(2)/2 h when the level of the side-coupled dot departs from the energy zero point.However,the linear conductance is always analogous to the MBS-absent case once the inter-MBS coupling comes into play.These findings provide new information about the leakage effect of MBSs in quantum-dot structures.
文摘Based on an investigation of existing methods for estimating fre- quency response functions(FRF)at home and abroad,two methods are ad- vanced.The one,denoted as H_(12),avoids underestimates at resonances and overestimates at antiresonances,while the other,denoted as H_F,regards the noise ratio of output to input as varying with the frequency.Finally,a soft- ware for estimating frequency response functions is introduced.A modal test for a steel plate excited with a random signal is made,and frequency response function estimates are made,making use of the above software.The test re- sults conform well with the theoretical analysis.
