Parity effects in the scaling of block entanglement in gapless spin chains.
Parity effects in the scaling of block entanglement in gapless spin chains.
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DOI：
10.1103/physrevlett.104.095701
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发表时间：
2009-11
影响因子：
8.6
通讯作者：
P. Calabrese;M. Campostrini;F. Essler;B. Nienhuis
中科院分区：
文献类型：
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作者：
P. Calabrese;M. Campostrini;F. Essler;B. Nienhuis
我们考虑Luttinger液体（LL）的Rényi α熵。对于大的块长度l，已知这些像lnl一样增长。我们发现，有subleading项，振荡频率为2k{F}（费米波数的LL），并表现出普遍的幂律衰减与l。新的临界指数等于K/（2alpha），其中K是LL参数。我们给出了各向异性XXZ模型的数值结果和自由费米子（XX）点的完全解析解。
We consider the Rényi alpha entropies for Luttinger liquids (LL). For large block lengths l, these are known to grow like lnl. We show that there are subleading terms that oscillate with frequency 2k{F} (the Fermi wave number of the LL) and exhibit a universal power-law decay with l. The new critical exponent is equal to K/(2alpha), where K is the LL parameter. We present numerical results for the anisotropic XXZ model and the full analytic solution for the free fermion (XX) point.