scholarly journals Ground state of the quantum symmetric finite-size XXZ spin chain with anisotropy parameter Delta = ½

2000 ◽  
Vol 33 (13) ◽  
pp. L121-L125 ◽  
Author(s):  
V Fridkin ◽  
Yu Stroganov ◽  
D Zagier
Keyword(s):  
Ground State ◽  
Spin Chain ◽  
Anisotropy Parameter ◽  
Finite Size

scholarly journals Motions of the String Solutions in the XXZ Spin Chain Under a Varying Twist

1997 ◽  
Vol 12 (04) ◽  
pp. 801-838 ◽  
Author(s):  
N. Fumita ◽  
H. Itoyama ◽  
T. Oota
Keyword(s):  
Ground State ◽  
Spin Chain ◽  
Imaginary Axis ◽  
Berry Phase ◽  
Numerical Study ◽  
Twist Angle ◽  
Finite Size ◽  
Bound State ◽  
Branch Points ◽  
Finite Size Corrections

We determine the motions of the roots of the Bethe ansatz equation for the ground state in the XXZ spin chain under a varying twist angle. This is done by analytic as well as numerical study in a finite size system. In the attractive critical regime 0 < Δ < 1, we reveal intriguing motions of strings due to the finite size corrections to the length of the strings: in the case of two-strings, the roots collide into the branch points perpendicularly to the imaginary axis, while in the case of three-strings, they fluctuate around the center of the string. These are successfully generalized to the case of n-string. These results are used to determine the final configuration of the momenta as well as that of the phase shift functions. We obtain these as well as the period and the Berry phase in the regime Δ ≤ -1 also, establishing the continuity of the previous results at -1 < Δ < 0 to this regime. We argue that the Berry phase can be used as a measure of the statistics of the quasiparticle (or the bound state) involved in the process.

BERRY PHASE AND CRITICAL BEHAVIOR OF THE XY SPIN CHAIN WITH THREE-SITE INTERACTION

2012 ◽  
Vol 26 (22) ◽  
pp. 1250141 ◽  
Author(s):  
HANLI LIAN
Keyword(s):  
Spin Chain ◽  
Berry Phase ◽  
Finite Size ◽  
Transverse Magnetic ◽  
Anomalous Behavior ◽  
Quantum Criticality ◽  
Critical Properties ◽  
Finite Size Scaling ◽  
Surrounding Environment ◽  
Xy Spin Chain

By calculating the Berry Phase (BP) of a central spin, the quantum criticality of the surrounding environment described by an XY spin chain with the three-site interaction in a transverse magnetic field is explored. The BP presents anomalous behavior along the critical region. The finite-size scaling behaviors suggest that the BP of the central spin can well capture the critical properties of the XY spin chain with the three-site interaction.

scholarly journals Effect of Single-Ion Anisotropy on Magnetocaloric Properties of Frustrated Spin-s Ising Nanoclusters

2020 ◽  
Vol 6 (4) ◽  
pp. 56
Author(s):  
Mariia Mohylna ◽  
Milan Žukovič
Keyword(s):  
Ground State ◽  
Anisotropy Parameter ◽  
State Behavior ◽  
Abrupt Decrease ◽  
Experimental Realization ◽  
Plane Anisotropy ◽  
Adiabatic Demagnetization ◽  
Magnetocaloric Properties ◽  
Cluster Geometry ◽  
Favorable Conditions

Effects of a single-ion anisotropy on magnetocaloric properties of selected spin-s≥1 antiferromagnetic Ising clusters with frustration-inducing triangular geometry are studied by exact enumeration. It is found that inclusion of the single-ion anisotropy parameter D can result in a much more complex ground-state behavior, which is also reflected in a magnetocaloric effect (MCE) at finite temperatures. For negative D (easy-plane anisotropy) with increasing s, the ground-state magnetization as a function of the external field gradually shows increasing number of plateaus of various heights. Except for the cases of integer s with D<D0≤0, the first magnetization plateau is of non-zero height. This property facilitates an enhanced MCE in the adiabatic demagnetization process in the form of an abrupt decrease in temperature as the magnetic field vanishes to zero. The cooling rate can be considerably enhanced in the systems with larger s and D>0 (easy-axis anisotropy), albeit its dependence on these parameters is strongly dependent on the cluster geometry. From the studied systems more favorable conditions for observing a giant MCE were found in the 2CS cluster, consisting of two corner-sharing tetrahedra, the experimental realization of which could be technologically used for efficient refrigeration to ultra-low temperatures.

scholarly journals Ground State of the Competing Spin Chain Cs2Cu2Mo3O12

2014 ◽  
Author(s):  
Yukihiro Hoshino ◽  
Soichiro Atarashi ◽  
Takayuki Goto ◽  
Masashi Hase ◽  
Takahiko Sasaki
Keyword(s):  
Ground State ◽  
Spin Chain

scholarly journals Irreversible work versus fidelity susceptibility for infinitesimal quenches

2017 ◽  
Vol 31 (06) ◽  
pp. 1750065 ◽  
Author(s):  
Simone Paganelli ◽  
Tony J. G. Apollaro
Keyword(s):  
Quantum System ◽  
Excited States ◽  
Ground State ◽  
Finite Size ◽  
Scaling Relations ◽  
Zero Temperature ◽  
Finite Size Scaling ◽  
Ising Chain ◽  
Extra Term ◽  
Explicit Relation

We compare the irreversible work produced in an infinitesimal sudden quench of a quantum system at zero temperature with its ground state fidelity susceptibility, giving an explicit relation between the two quantities. We find that the former is proportional to the latter but for an extra term appearing in the irreversible work which includes also contributions from the excited states. We calculate explicitly the two quantities in the case of the quantum Ising chain, showing that at criticality they exhibit different scaling behaviors. The irreversible work, rescaled by square of the quench’s amplitude, exhibits a divergence slower than that of the fidelity susceptibility. As a consequence, the two quantities obey also different finite-size scaling relations.

Sign in / Sign up

Export Citation Format

Share Document