Cavity magnomechanics has recently become a new platform for studying macroscopic quantum phenomena.The magnetostriction induced vibration mode of a large-size ferromagnet or ferrimagnet reaching its ground state repr...Cavity magnomechanics has recently become a new platform for studying macroscopic quantum phenomena.The magnetostriction induced vibration mode of a large-size ferromagnet or ferrimagnet reaching its ground state represents a genuine macroscopic quantum state.Here we study the ground-state cooling of the mechanical vibration mode in a cavity magnomechanical system,and focus on the role of magnon squeezing in improving the cooling efficiency.The magnon squeezing is obtained by exploiting the magnon self-Kerr nonlinearity.We find that the magnon squeezing can significantly and even completely suppress the magnomechanical Stokes scattering.It thus becomes particularly useful in realizing ground-state cooling in the unresolved-sideband regime,where the conventional sideband cooling protocols become inefficient.We also find that the coupling to the microwave cavity plays only an adverse effect in mechanical cooling.This makes essentially the two-mode magnomechanical system(without involving the microwave cavity)a preferred system for cooling the mechanical motion,in which the magnon mode is established by a uniform bias magnetic field and a microwave drive field.展开更多
We theoretically explore the tunability of magnomechanically induced transparency(MMIT) phenomenon and fastslow light effect in a hybrid cavity magnomechanical system in which a high-quality yttrium iron garnet(YIG) s...We theoretically explore the tunability of magnomechanically induced transparency(MMIT) phenomenon and fastslow light effect in a hybrid cavity magnomechanical system in which a high-quality yttrium iron garnet(YIG) sphere and an atomic ensemble are placed inside a microwave cavity. In the probe output spectrum, we can observe magnoninduced transparency(MIT) and MMIT due to the photon-magnon and phonon-magnon couplings. We further investigate the effect of atomic ensemble on the absorption spectrum. The results show that better transparency can be obtained by choosing appropriate atomic ensemble parameters. We give an explicit explanation for the mechanism of the Fano resonance phenomenon. Moreover, we discuss phenomena of slow-light propagation. The maximum group delay increases significantly with the increasing atom–cavity coupling strength, and the conversion between slow light and fast light can also be achieved by adjusting the atom–cavity coupling strength. These results may have potential applications for quantum information processing and high precision measurements.展开更多
A magnonic counterpart to optical frequency combs is vital for high-precision magnonic frequency metrology and spectroscopy.Here,we present an efficient mechanism for the generation of robust magnonic frequency combs ...A magnonic counterpart to optical frequency combs is vital for high-precision magnonic frequency metrology and spectroscopy.Here,we present an efficient mechanism for the generation of robust magnonic frequency combs in a yttrium iron garnet(YIG)sphere via magnetostrictive effects.We show that magnonic and vibrational dynamics in the ferrimagnetic sphere can be substantively modified in the presence of magnetostrictive effects,which results in degenerate and non-degenerate magnonic four-wave mixing and frequency conversion.Particularly,resonantly enhanced magnetostrictive effects can induce phonon laser action above a threshold,which leads to significant magnonic nonlinearity and enables a potentially practical scheme for the generation of robust magnonic frequency combs.Numerical calculations of both magnonic and phononic dynamics show excellent agreement with this theory.These results deepen our understanding of magnetostrictive interaction,open a novel and efficient pathway to realize magnonic frequency conversion and mixing in a magnonic device,and provide a sensitive tool for precision measurement.展开更多
The ringing phenomenon has been studied in optical whispering gallery mode(WGM)resonators and can be used to sense the ultrafast process in spectroscopy.Here we observe the ringing phenomenon in a magnomechanical syst...The ringing phenomenon has been studied in optical whispering gallery mode(WGM)resonators and can be used to sense the ultrafast process in spectroscopy.Here we observe the ringing phenomenon in a magnomechanical system for the first time,which is induced by the interference between the microwave photons converted from the damped phonons and the probing microwave photons.This interference eventually appears as a transparency window even along with the ringing phenomenon in the measured microwave reflection spectrum,which is influenced by the scanning speed and the input power.Then,the ringing spectroscopy is used to measure the coupling strength between the magnon and phonon modes,and outline the displacement profile of𝑆1,2,2 mechanical mode in a YIG microsphere,demonstrating the theoretical analysis.In addition,the ring-up spectroscopy is developed in our magnomechanical system,laying the foundation for fast sensing based on mechanical motion.展开更多
We propose to realize the ground state cooling of magnomechanical resonator in a parity-time(PT).symmetric cavity magnomechanical system composed of a loss ferromagnetic sphere and a gain microwave cavity.In the schem...We propose to realize the ground state cooling of magnomechanical resonator in a parity-time(PT).symmetric cavity magnomechanical system composed of a loss ferromagnetic sphere and a gain microwave cavity.In the scheme,the magnomechanical resonator can be cooled close to its ground state via the magnomechanical interaction,and it is found that the cooling effect in PT-symmetric system is much higher than that in non-PT-symmetric system.Resorting to the magnetic force noise spectrum,we investigate the final mean phonon number with experimentally feasible parameters and find surprisingly that the ground state cooling of magnomechanical resonator can be directly achieved at room temperature.Furthermore,we also illustrate that the ground state cooling can be flexibly controlled via the external magnetic field.展开更多
基金supported by Zhejiang Province Program for Science and Technology(2020C01019)the National Natural Science Foundation of China(U1801661,11874249,11934010,12174329).
文摘Cavity magnomechanics has recently become a new platform for studying macroscopic quantum phenomena.The magnetostriction induced vibration mode of a large-size ferromagnet or ferrimagnet reaching its ground state represents a genuine macroscopic quantum state.Here we study the ground-state cooling of the mechanical vibration mode in a cavity magnomechanical system,and focus on the role of magnon squeezing in improving the cooling efficiency.The magnon squeezing is obtained by exploiting the magnon self-Kerr nonlinearity.We find that the magnon squeezing can significantly and even completely suppress the magnomechanical Stokes scattering.It thus becomes particularly useful in realizing ground-state cooling in the unresolved-sideband regime,where the conventional sideband cooling protocols become inefficient.We also find that the coupling to the microwave cavity plays only an adverse effect in mechanical cooling.This makes essentially the two-mode magnomechanical system(without involving the microwave cavity)a preferred system for cooling the mechanical motion,in which the magnon mode is established by a uniform bias magnetic field and a microwave drive field.
基金the National Natural Science Foundation of China (Grant No. 62061028)the Opening Project of Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology (Grant No. ammt2021A4)+4 种基金the Foundation for Distinguished Young Scientists of Jiangxi Province (Grant No. 20162BCB23009)the Open Research Fund Program of the State Key Laboratory of LowDimensional Quantum Physics (Grant No. KF202010)the Interdisciplinary Innovation Fund of Nanchang University (Grant No. 9166-27060003-YB12)the Open Research Fund Program of Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education (Grant No. OEIAM202004)the Graduate Innovation Special Fund of Jiangxi Province (Grant No. YC2021-S054)。
文摘We theoretically explore the tunability of magnomechanically induced transparency(MMIT) phenomenon and fastslow light effect in a hybrid cavity magnomechanical system in which a high-quality yttrium iron garnet(YIG) sphere and an atomic ensemble are placed inside a microwave cavity. In the probe output spectrum, we can observe magnoninduced transparency(MIT) and MMIT due to the photon-magnon and phonon-magnon couplings. We further investigate the effect of atomic ensemble on the absorption spectrum. The results show that better transparency can be obtained by choosing appropriate atomic ensemble parameters. We give an explicit explanation for the mechanism of the Fano resonance phenomenon. Moreover, we discuss phenomena of slow-light propagation. The maximum group delay increases significantly with the increasing atom–cavity coupling strength, and the conversion between slow light and fast light can also be achieved by adjusting the atom–cavity coupling strength. These results may have potential applications for quantum information processing and high precision measurements.
文摘A magnonic counterpart to optical frequency combs is vital for high-precision magnonic frequency metrology and spectroscopy.Here,we present an efficient mechanism for the generation of robust magnonic frequency combs in a yttrium iron garnet(YIG)sphere via magnetostrictive effects.We show that magnonic and vibrational dynamics in the ferrimagnetic sphere can be substantively modified in the presence of magnetostrictive effects,which results in degenerate and non-degenerate magnonic four-wave mixing and frequency conversion.Particularly,resonantly enhanced magnetostrictive effects can induce phonon laser action above a threshold,which leads to significant magnonic nonlinearity and enables a potentially practical scheme for the generation of robust magnonic frequency combs.Numerical calculations of both magnonic and phononic dynamics show excellent agreement with this theory.These results deepen our understanding of magnetostrictive interaction,open a novel and efficient pathway to realize magnonic frequency conversion and mixing in a magnonic device,and provide a sensitive tool for precision measurement.
基金supported by the National Key Research and Development Program of China(2020YFB2205801)Innovation program for Quantum Science and Technology(2021ZD0303203)+2 种基金National Natural Science Foundation of China(11934012,11874342 and 92050109)USTC Research Funds of the Double First-Class Initiative(YD2470002002)the Fundamental Research Funds for the Central Universities.
文摘The ringing phenomenon has been studied in optical whispering gallery mode(WGM)resonators and can be used to sense the ultrafast process in spectroscopy.Here we observe the ringing phenomenon in a magnomechanical system for the first time,which is induced by the interference between the microwave photons converted from the damped phonons and the probing microwave photons.This interference eventually appears as a transparency window even along with the ringing phenomenon in the measured microwave reflection spectrum,which is influenced by the scanning speed and the input power.Then,the ringing spectroscopy is used to measure the coupling strength between the magnon and phonon modes,and outline the displacement profile of𝑆1,2,2 mechanical mode in a YIG microsphere,demonstrating the theoretical analysis.In addition,the ring-up spectroscopy is developed in our magnomechanical system,laying the foundation for fast sensing based on mechanical motion.
基金the National Natural Science Foundation of China under Grant No.61822114.
文摘We propose to realize the ground state cooling of magnomechanical resonator in a parity-time(PT).symmetric cavity magnomechanical system composed of a loss ferromagnetic sphere and a gain microwave cavity.In the scheme,the magnomechanical resonator can be cooled close to its ground state via the magnomechanical interaction,and it is found that the cooling effect in PT-symmetric system is much higher than that in non-PT-symmetric system.Resorting to the magnetic force noise spectrum,we investigate the final mean phonon number with experimentally feasible parameters and find surprisingly that the ground state cooling of magnomechanical resonator can be directly achieved at room temperature.Furthermore,we also illustrate that the ground state cooling can be flexibly controlled via the external magnetic field.