A new correlator in quantum spin chains
نویسندگان
چکیده
We propose a new correlator in one-dimensional quantum spin chains, the s−Emptiness Formation Probability (s−EFP). This is a natural generalization of the Emptiness Formation Probability (EFP), which is the probability that the first n spins of the chain are all aligned downwards. In the s−EFP we let the spins in question be separated by s sites. The usual EFP corresponds to the special case when s = 1, and taking s > 1 allows us to quantify non-local correlations. We express the s−EFP for the anisotropic XY model in a transverse magnetic field, a system with both critical and non-critical regimes, in terms of a Toeplitz determinant. For the isotropic XY model we find that the magnetic field induces an interesting length scale. PACS numbers: 75.10.Pq, 02.30.Ik, 73.43.Nq
منابع مشابه
Formfactors and Functional Form of Correlators in the Xx-spin Chain
We present the new expressions for the formfactors of local operators for the XX-quantum spin chain as a Cauchy determinants. Using the known functional form of the correlator at large distances we propose the new expression for the constant for the asymptotics of the correlator as a Cauchy determinant. We calculate the momentum distribution for the general case of the XXZ-spin chain and point ...
متن کاملNew QCD Sum Rules for Nucleon Tensor Charge∗
Two new QCD sum rules for nucleon tensor charge are derived from a mixed correlator of spin-1/2 and spin-3/2 nucleon interpolating fields. These sum rules are analyzed along with a sum rule obtained from the usual correlator of a general spin-1/2 nucleon interpolating field. The validity and reliability of the sum rules are examined by monitoring the contaminations arising from the transitions ...
متن کاملThe Quantum Statistical Mechanical Theory of Transport Processes
A new derivation of the quantum Boltzmann transport equation for the Fermion system from the quantum time evolution equation for the wigner distribution function is presented. The method exhibits the origin of the time - irreversibility of the Boltzmann equation. In the present work, the spin dependent and indistinguishibility of particles are also considered.
متن کاملOn the second-neighbor correlator in 1D XXX quantum antiferromagnetic spin chain
We have calculated the energy per site for the ground state of antiferromagnetic quantum spin chain with variable range exchange h(j − k) ∝ sinh a sinh a(j − k) in the framework of the asymptotic Bethe ansatz. By expanding it in powers of e, we have confirmed the value of the second-neighbor correlator for the model with nearest-neighbor exchange obtained earlier in the atomic limit of the Hubb...
متن کاملNeutron Scattering Study of Quantum Phase Transitions in Integral Spin Chains
Quite a few low-dimensional magnets are quantum-disordered “spin liquids” with a characteristic gap in the magnetic excitation spectrum. Among these are antiferromagnetic chains of integer quantum spins. Their generic feature are long-lived massive (gapped) excitations (magnons) that are subject to Zeeman splitting in external magnetic fields. The gap in one of the magnon branches decreases wit...
متن کامل