Bose glass behavior in(Yb1−xLux)4As3representing randomly diluted quantum spin-

G. Kamieniarz

¹

,

R. Matysiak

²

,

P. Gegenwart

³

et al.

Abstract

Bose glass behavior in (Yb 1−x Lu x ) 4 As 3 representing the randomly diluted quantum spin-1/2 chains The site-diluted compound (Yb1−xLux)4As3 is a scarce realization of the linear Heisenberg antiferromagnet partitioned into finite-size segments and is an ideal model compound for studying field-dependent effects of quenched disorder in the one-dimensional antiferromagnets. It differentiates from the systems studied so far in two aspects -the type of randomness and the nature of the energy gap in the pure sample. We have measured the specific heat of single-crystal (Yb1−xLux)4As3 in magnetic fields up to 19.5 T. The contribution C ⊥ arising from the magnetic subsystem in an applied magnetic field perpendicular to the chains is determined. Compared to pure Yb4As3, for which C ⊥ indicates a gap opening, for diluted systems a non-exponential decay is found at low temperatures which is consistent with the thermodynamic scaling of the specific heat established for a Bose-glass phase.

Вариационная Модель Низкоразмерного Магнетика

“…Пробная волновая функция для кластеров длиной 4 узла в явном виде может быть представлена как |ψ = gẐ 0 0 gẐ 3 3 gẐ 5 5 gẐ 6 6 gẐ 9 9 gẐ a a gẐ c c gẐ e e gẐ f f gM m |ψ 0 ,…”

“…Гейзенберговская цепочка спина 1/2 является одной из фундаментальных и наиболее тщательно исследованных моделей магнетизма [4]: известны строгие решения методом анзаца Бете, а также различные аналитические и численные методы. При этом в последнее время в 1D-цепочках были обнаружены новые экзотические состояния: основное состояние с симметрией E8 в поперечном магнитном поле в CoNb 2 O 6 [5], бозе-стекло в (Yb 1−x Lu x ) 4 As 3 [6] и т. д.…”

Dirty bosons on the Cayley tree: Bose-Einstein condensation versus ergodicity breaking

“…It can be described as an inhomogeneous gapless compressible fluid with short-ranged correlations preventing any global phase coherence responsible of delocalization properties. Known as the "dirty boson" problem, the localized Bose glass phase and its transition from a delocalized superfluid have been theoretically and numerically studied from one to three dimensions in various contexts , and also reported in several experimental setups, from disordered superconductors [79][80][81][82][83] to trapped ultracold atoms [84][85][86][87], as well as chemically doped antiferromagnetic spin compounds [88][89][90][91][92][93][94][95][96][97].…”

Numerical study of the temperature dependence of the NMR relaxation rate across the superfluid–Bose glass transition in one dimension

“…It has also been observed in an array of quasi-one-dimensional samples of 39 K cold atoms, subject to a quasiperiodic optical lattice [14]. Another type of systems in which the Bose glass phase has been investigated are antiferromagnetic Mott insulators [15][16][17][18] such as the spin-1/2 ladder compound (CH 3 ) 2 CHNH 3 Cu(Cl x Br 1−x ) 3 [19] and the Br doped spin-1 system Ni(Cl 1−x Br x ) 2 -4SC(NH 2 ) 2 [20][21][22][23][24][25][26][27] to cite but a few [28,29].…”