scholarly journals Controlling the metal-to-insulator relaxation of the metastable hidden quantum state in 1T-TaS2

2015 ◽  
Vol 1 (6) ◽  
pp. e1500168 ◽  
Author(s):  
Igor Vaskivskyi ◽  
Jan Gospodaric ◽  
Serguei Brazovskii ◽  
Damjan Svetin ◽  
Petra Sutar ◽  
...  

Controllable switching between metastable macroscopic quantum states under nonequilibrium conditions induced either by light or with an external electric field is rapidly becoming of great fundamental interest. We investigate the relaxation properties of a “hidden” (H) charge density wave (CDW) state in thin single crystals of the layered dichalcogenide 1T-TaS2, which can be reached by either a single 35-fs optical laser pulse or an ~30-ps electrical pulse. From measurements of the temperature dependence of the resistivity under different excitation conditions, we find that the metallic H state relaxes to the insulating Mott ground state through a sequence of intermediate metastable states via discrete jumps over a “Devil’s staircase.” In between the discrete steps, an underlying glassy relaxation process is observed, which arises because of reciprocal-space commensurability frustration between the CDW and the underlying lattice. We show that the metastable state relaxation rate may be externally stabilized by substrate strain, thus opening the way to the design of nonvolatile ultrafast high-temperature memory devices based on switching between CDW states with large intrinsic differences in electrical resistance.

1993 ◽  
Vol 07 (23n24) ◽  
pp. 3973-4003 ◽  
Author(s):  
P. FOURY ◽  
J.P. POUGET

The structural instabilities towards the formation of a charge density wave (CDW) ground state exhibited by several layered Mo and W bronzes and oxides are reviewed. It is shown that in these two-dimensional (2D) metals, including the purple bronzes A x Mo 6 O 17 (A=K, Na, Tl; x≈1), the γ and η phases of MO 4 O 11 and the monophosphate tungsten bronzes with pentagonal tunnels ( PO 2)4 ( WO 3)2m(m=4, 6, 7), the CDW instability can be associated with particular chains of MoO 6 or WO 6 octahedra of the ReO 3 type slabs along which there is a strong overlap of the t 2g orbitals. The CDW critical wave vectors of the purple bronzes, Mo 4 O 11 and the tungsten bronzes with m=4 and 6 lead to a common nesting between differently oriented 1D Fermi surfaces. It is suggested that the anharmonic CDW modulation, which occurs in the tungsten bronzes with m≥7, could be the structural fingerprint of electron localization effects.


2004 ◽  
Vol 69 (12) ◽  
Author(s):  
D. Graf ◽  
J. S. Brooks ◽  
E. S. Choi ◽  
S. Uji ◽  
J. C. Dias ◽  
...  

2002 ◽  
Vol 16 (20n22) ◽  
pp. 3156-3163 ◽  
Author(s):  
A. POLKOVNIKOV ◽  
S. SACHDEV ◽  
M. VOJTA ◽  
E. DEMLER

Recent neutron scattering, nuclear magnetic resonance, and scanning tunneling microscopy experiments have yielded valuable new information on the interplay between charge and spin density wave order and superconductivity in the cuprate superconductors, by using a perpendicular magnetic field to tune the ground state properties. We compare the results of these experiments with the predictions of a theory which assumed that the ordinary superconductor was proximate to a quantum transition to a superconductor with co-existing spin/charge density wave order.


2020 ◽  
Vol 6 (13) ◽  
pp. eaax9480 ◽  
Author(s):  
A. Ribak ◽  
R. Majlin Skiff ◽  
M. Mograbi ◽  
P. K. Rout ◽  
M. H. Fischer ◽  
...  

Van der Waals materials offer unprecedented control of electronic properties via stacking of different types of two-dimensional materials. A fascinating frontier, largely unexplored, is the stacking of strongly correlated phases of matter. We study 4Hb-TaS2, which naturally realizes an alternating stacking of 1T-TaS2 and 1H-TaS2 structures. The former is a well-known Mott insulator, which has recently been proposed to host a gapless spin-liquid ground state. The latter is a superconductor known to also host a competing charge density wave state. This raises the question of how these two components affect each other when stacked together. We find a superconductor with a Tc of 2.7 Kelvin and anomalous properties, of which the most notable one is a signature of time-reversal symmetry breaking, abruptly appearing at the superconducting transition. This observation is consistent with a chiral superconducting state.


2016 ◽  
Vol 113 (51) ◽  
pp. 14645-14650 ◽  
Author(s):  
H. Jang ◽  
W.-S. Lee ◽  
H. Nojiri ◽  
S. Matsuzawa ◽  
H. Yasumura ◽  
...  

The existence of charge-density-wave (CDW) correlations in cuprate superconductors has now been established. However, the nature of the CDW ground state has remained uncertain because disorder and the presence of superconductivity typically limit the CDW correlation lengths to only a dozen unit cells or less. Here we explore the field-induced 3D CDW correlations in extremely pure detwinned crystals of YBa2Cu3O2(YBCO) ortho-II and ortho-VIII at magnetic fields in excess of the resistive upper critical field (Hc2) where superconductivity is heavily suppressed. We observe that the 3D CDW is unidirectional and possesses a long in-plane correlation length as well as significant correlations between neighboring CuO2planes. It is significant that we observe only a single sharply defined transition at a critical field proportional toHc2, given that the field range used in this investigation overlaps with other high-field experiments including quantum oscillation measurements. The correlation volume is at least two to three orders of magnitude larger than that of the zero-field CDW. This is by far the largest CDW correlation volume observed in any cuprate crystal and so is presumably representative of the high-field ground state of an “ideal” disorder-free cuprate.


1994 ◽  
Vol 375 ◽  
Author(s):  
Kevin E. Smith ◽  
Klaus Breuer ◽  
David Goldberg ◽  
Martha Greenblatt ◽  
William McCarroll ◽  
...  

AbstractThe electronic structure of the prototypical quasi-one dimensional (1D) conductor K03MoO3 has been studied using high resolution photoemission spectroscopy. In particular, the electronic structure of defects was investigated in order to understand the mechanism for charge density wave pinning and destruction of the Peierls transition. Defects were found to radically alter the electronic structure close to the Fermi level (EF), thus strongly modifying the structure of the Fermi surface. While a low emission intensity at EF has been interpreted as evidence for a Luttinger liquid ground state in a ID metal, we show that non-stoichiometric surfaces lead to similar effects. The nature of the ground state is discussed in the context of these results.


Sign in / Sign up

Export Citation Format

Share Document