Using the determinant representation for the field-field correlation functions of impenetrable anyons at finite temperature obtained in a previous paper, we derive a system of nonlinear partial differential equations completely characterizing the correlators. The system is the same as the one for impenetrable bosons but with different initial conditions. The large-distance asymptotic behavior of the correlation functions is obtained from the analysis of the Riemann-Hilbert problem associated with the system of differential equations. We calculate both the exponential and pre-exponential factors in the asymptotics of the field-field correlators. The asymptotics derived in this way agree with those of the free fermions and impenetrable bosons in the appropriate limits,
κ→1 and
κ→0, of the statistics parameter
κ, and coincide with the predictions of the conformal field theory at low temperatures.
We consider the quantum Non-linear Schrödinger equation
i∂tΨ=−∂x2Ψ+2cΨ†Ψ2 with positive coupling constant
c varying from zero to infinity. We study quantum correlation functions of this model using the determinant representation of these correlation functions. We consider the case of a finite density ground state and evaluate, using the Riemann Hilbert problem, the asymptotics of the probability that no particles are present in the space interval
[0,x] in the large
x limit. We call this the probability of phase separation or alternately the emptiness formation probability.