A quantum phase transition from triangular to stripe charge order in NbSe${}_2$

Abstract

The competition between proximate electronic phases produces a complex phenomenology in strongly correlated systems. In particular, fluctuations associated with periodic charge or spin modulations, known as density waves, may lead to exotic superconductivity in several correlated materials. However, density waves have been difficult to isolate in the presence of chemical disorder, and the suspected causal link between competing density wave orders and high temperature superconductivity is not understood. Here we use scanning tunneling microscopy to image a previously unknown unidirectional (stripe) charge density wave (CDW) smoothly interfacing with the familiar tri-directional (triangular) CDW on the surface of the stoichiometric superconductor NbSe${}_2$. Our low temperature measurements rule out thermal fluctuations, and point to local strain as the tuning parameter for this quantum phase transition. We use this discovery to resolve two longstanding debates about the anomalous spectroscopic gap and the role of Fermi surface nesting in the CDW phase of NbSe${}_2$. Our results highlight the importance of local strain in governing phase transitions and competing phenomena, and suggest a new direction of inquiry for resolving similarly longstanding debates in cuprate superconductors and other strongly correlated materials.

PNAS in press

References in corpus (12)

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• Charge density wave origin of cuprate checkerboard visualized by scanning tunneling microscopy
• Momentum-Resolved Landau-Level Spectroscopy of Dirac Surface State in Bi2Se3
• Appearance of fluctuating stripes at the onset of the pseudogap in the high-Tc Superconductor Bi2Sr2CaCu2O8+x
• Two energy gaps and Fermi surface 'arcs' in NbSe2
• Quasi-Particle Spectra, Charge-Density-Wave, Superconductivity and Electron-Phonon Coupling in 2H-NbSe2
• Imaging the impact on cuprate superconductivity of varying the inter-atomic distances within individual crystal unit-cells
• Modeling the Fermi arc in underdoped cuprates
• Distinguishing Patterns of Charge Order: Stripes or Checkerboards
• A distinct bosonic mode in an electron-doped high-transition-temperature superconductor
• From stripe to checkerboard order on the square lattice in the presence of quenched disorder
• Primary role of the barely occupied states in the charge density wave formation of NbSe2

Cited by in corpus (17)

• Classification of Charge Density Waves Based on Their Nature
• Pseudogap from ARPES experiment: three gaps in cuprates and topological superconductivity
• Charge Order from Orbital-dependent Coupling Evidenced by NbSe${}_2$
• Pressure dependence of superconducting critical temperature and upper critical field of 2H-NbS2
• Stripe and short range order in the charge density wave of 1T-Cu${}_x$TiSe${}_2$
• Impact of Electron-Hole Correlations on the 1T-TiSe2 Electronic Structure
• Strain Engineering a $4a\times \sqrt{3}a$ Charge Density Wave Phase in Transition Metal Dichalcogenide 1T-VSe${}_2$
• Checkerboard stripe electronic state on cleaved surface of NdO${}_{0.7}$F${}_{0.3}$BiS${}_2$ probed by scanning tunneling microscope
• Quasiparticle energy bands and Fermi surfaces of monolayer NbSe${}_2$
• Multiple Charge Density Wave States at the Surface of TbTe${}_3$
• Granular superconductivity below 5~K in SPI-II pyrolytic graphite
• Quantum phase transition in few-layer NbSe${}_2$ probed through quantized conductance fluctuations
• Charge density wave modulation and gap measurements in CeTe${}_3$
• Superconducting energy gap of $2H$-NbSe${}_2$ in phonon spectroscopy
• Gutzwiller Charge Phase Diagram of Cuprates, including Electron-Phonon Coupling Effects
• S-shaped suppression of the superconducting transition temperature in Cu-intercalated NbSe2
• Self-organized electronic superlattices in layered materials