Mott transition, compressibility divergence, and the P-T phase diagram of layered organic superconductors:: An ultrasonic investigation -: art. no. 127002
Mott transition, compressibility divergence, and the P-T phase diagram of layered organic superconductors:: An ultrasonic investigation -: art. no. 127002
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DOI：
10.1103/physrevlett.90.127002
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发表时间：
2003-03-28
影响因子：
8.6
通讯作者：
Truong, KD
中科院分区：
文献类型：
--
作者：
Fournier, D;Poirier, M;Truong, KD
本文用超声声速测量法研究了有机超导体kappa-（BEDT-TTF）（2）Cu[N（CN）（2）]Cl在氦气压力下的相图。不同的相变，确定了通过几个弹性异常特征等压和等温扫描。我们的数据揭示了两个交叉线的临界点上终止的一阶莫特过渡线。当临界点接近沿着这些线，我们观察到一个戏剧性的异常的声速，这是一致的发散压缩性的电子自由度。
The phase diagram of the organic superconductor kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Cl has been investigated by ultrasonic velocity measurements under helium gas pressure. Different phase transitions were identified through several elastic anomalies characterized from isobaric and isothermal sweeps. Our data reveal two crossover lines that end on the critical point terminating the first-order Mott transition line. When the critical point is approached along these lines, we observe a dramatic anomaly of the sound velocity which is consistent with a diverging compressibility of the electronic degrees of freedom.