The reaction abilities of structural units in Fe-C binary melts over a temperature range above the liquidus lines have been evaluated by a thermodynamic model for calculating the mass action concentrations Ni of struc...The reaction abilities of structural units in Fe-C binary melts over a temperature range above the liquidus lines have been evaluated by a thermodynamic model for calculating the mass action concentrations Ni of structural units in Fe-C binary melts based on the atom-molecule coexistence theory （AMCT）, i.e., the AMCT-N/model, through comparing with the predicted activities aR.i of both C and Fe by 14 collected models from the literature at four temperatures of 1833, 1873, 1923, and 1973 K. Furthermore, the Raoultian activity coefficient γC0 of in infinitely dilute Fe-C binary melts and the standard molar Gibbs free energy change △solG%m,Cdis（1）→[C]W[C]=1.0 of dissolved liquid C for forming w[C] as 1.0 in Fe-C binary melts referred to 1 mass% of C as reference state have also been determined to be valid. The determined activity coefficient In γC of C and activity coefficient In TEe of Fe including temperature effect for Fe-C binary melts can be described by a quadratic polynomial function and a cubic polynomial function, respectively.展开更多
In the present paper, we investigate the instability, adiabaticity, and controlling effects of external fields for a dark state in a homonuclear atom-tetramer conversion that is implemented by a generalized stimulated...In the present paper, we investigate the instability, adiabaticity, and controlling effects of external fields for a dark state in a homonuclear atom-tetramer conversion that is implemented by a generalized stimulated Raman adiabatic passage. We analytically obtain the regions for the appearance of dynamical instability and study the adiabatic evolution by a newly defined adiabatic fidelity. Moreover, the effects of the external field parameters and the spontaneous emissions on the conversion efficiency are also investigated.展开更多
We investigate the quantum many-body dynamics of ultracold atom–molecule conversion using a Floquet spin-boson model,where the periodic energy detuning between molecules and atomic pairs is utilized to explore variou...We investigate the quantum many-body dynamics of ultracold atom–molecule conversion using a Floquet spin-boson model,where the periodic energy detuning between molecules and atomic pairs is utilized to explore various dynamical regimes.We find that the upper bound of the adiabatic driving frequency increases continuously with the strength of molecule–molecule interactions,indicating that many-body interactions are beneficial in meeting the requirement of the adiabatic condition,thereby facilitating the realization of adiabatic atom–molecule conversion.This enhancement of the fulfillment of the adiabatic condition is further evidenced by the stabilization of periodic oscillations in the mean molecule number over time,protected by these interactions,even when the frequency lies within the localized regime.Interestingly,in the diffusive regime,while the many-body interaction has little effect on the dynamical equilibrium of atom–molecule conversion,it significantly expands the diffusive regime.In the high-frequency limit,many-body interactions are found to completely suppress atom–molecule conversion.Our results shed light on how molecule–molecule interactions influence the boundaries between different dynamical regimes.展开更多
基金This work is supported by the Beijing Natural Science Foundation （Grant No. 2182069） and the National Natural Science Foundation of China （Grant No. 51174186）.
文摘The reaction abilities of structural units in Fe-C binary melts over a temperature range above the liquidus lines have been evaluated by a thermodynamic model for calculating the mass action concentrations Ni of structural units in Fe-C binary melts based on the atom-molecule coexistence theory （AMCT）, i.e., the AMCT-N/model, through comparing with the predicted activities aR.i of both C and Fe by 14 collected models from the literature at four temperatures of 1833, 1873, 1923, and 1973 K. Furthermore, the Raoultian activity coefficient γC0 of in infinitely dilute Fe-C binary melts and the standard molar Gibbs free energy change △solG%m,Cdis（1）→[C]W[C]=1.0 of dissolved liquid C for forming w[C] as 1.0 in Fe-C binary melts referred to 1 mass% of C as reference state have also been determined to be valid. The determined activity coefficient In γC of C and activity coefficient In TEe of Fe including temperature effect for Fe-C binary melts can be described by a quadratic polynomial function and a cubic polynomial function, respectively.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11005055,11075020,and 11204117)the National Fundamental Research Programme of China(Grant No.2011CB921503)+1 种基金the Ph.D.Programs Foundation of Liaoning Provincial Science and Technology Bureau(GrantNo.201103778)the Higher School Excellent Researcher Award Program from the Educational Department of Liaoning Province of China(GrantNo.LJQ2011005)
文摘In the present paper, we investigate the instability, adiabaticity, and controlling effects of external fields for a dark state in a homonuclear atom-tetramer conversion that is implemented by a generalized stimulated Raman adiabatic passage. We analytically obtain the regions for the appearance of dynamical instability and study the adiabatic evolution by a newly defined adiabatic fidelity. Moreover, the effects of the external field parameters and the spontaneous emissions on the conversion efficiency are also investigated.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.12375019 and 11974273)Shanxi Agricultural University Introduction of Talent Research Start-up Project Grant(Grant No.2024BQ11)the Research Funding and Reward for Doctoral Graduates Researchers Coming to Work in Shanxi Province(Grant No.SXBYKY2024050).
文摘We investigate the quantum many-body dynamics of ultracold atom–molecule conversion using a Floquet spin-boson model,where the periodic energy detuning between molecules and atomic pairs is utilized to explore various dynamical regimes.We find that the upper bound of the adiabatic driving frequency increases continuously with the strength of molecule–molecule interactions,indicating that many-body interactions are beneficial in meeting the requirement of the adiabatic condition,thereby facilitating the realization of adiabatic atom–molecule conversion.This enhancement of the fulfillment of the adiabatic condition is further evidenced by the stabilization of periodic oscillations in the mean molecule number over time,protected by these interactions,even when the frequency lies within the localized regime.Interestingly,in the diffusive regime,while the many-body interaction has little effect on the dynamical equilibrium of atom–molecule conversion,it significantly expands the diffusive regime.In the high-frequency limit,many-body interactions are found to completely suppress atom–molecule conversion.Our results shed light on how molecule–molecule interactions influence the boundaries between different dynamical regimes.
