Lateral quantum confinement effect on monolayer high-Tc superconductors
arXiv:2303.17353 · doi:10.1021/acs.nanolett.4c01435
Abstract
Despite decades of research in spatially confined superconducting systems to understand the modification of superconductivity from reduced length scales, the investigation of the quantum confinement effect on high-temperature superconductors remains an outstanding challenge. Here, we report scanning tunneling spectroscopy measurements on laterally confined FeSe monolayers on SrTiO3 substrates, which are formed by epitaxially growing FeSe films with a coverage less than one unit cell. Comparing to the uniform regions of FeSe monolayers, the peninsula regions at the monolayer boundary exhibit reduced Fermi energy and undiminished superconductivity, leading to a putative crossover from a Bardeen-Cooper-Schrieffer state to a Bose-Einstein condensate state. In isolated FeSe monolayer islands, superconductivity is shown to exist in samples of smaller volume in contrast to conventional superconductors, while the validity of Anderson's criterion remains fulfilled. Our work reveals lateral quantum confinement effects in unconventional superconductors, to enrich the understanding of high-temperature superconductivity in low-dimensional systems.
References in corpus (35)
- Interface induced high temperature superconductivity in single unit-cell FeSe films on SrTiO3
- Scanning tunneling spectroscopy of high-temperature superconductors
- BCS-BEC Crossover: From High Temperature Superconductors to Ultracold Superfluids
- Field-induced superconducting phase of FeSe in the BCS-BEC cross-over
- Discovery of Orbital-Selective Cooper Pairing in FeSe
- Two-Band Superconductivity in MgB2
- Direct observation of high temperature superconductivity in one-unit-cell FeSe films
- BCS-BEC Crossover and the Unitary Fermi Gas
- Anomalous metals -- failed superconductors
- Plain s-wave superconductivity in single-layer FeSe on SrTiO3 probed by scanning tunneling microscopy
- Size Dependent Breakdown of Superconductivity in Ultranarrow Nanowires
- Observation of shell effects in superconducting nanoparticles of Sn
- Quantum coherence across bosonic superconductor-anomalous metal-insulator transitions
- Size dependence of the Tc and the superconducting energy gap in nanocrystalline thin films of Nb
- Evolution of Microscopic Localization in Graphene in a Magnetic Field from Scattering Resonances to Quantum Dots
- Resonant and crossover phenomena in a multiband superconductor tuning the chemical potential near a band edge
- Giant superconducting fluctuations in the compensated semimetal FeSe at the BCS-BEC crossover
- Gate-controlled BCS-BEC crossover in a two-dimensional superconductor
- Origin of charge transfer and enhanced electron-phonon coupling in single unit-cell FeSe films on SrTiO3
- Atomic line defects and zero-energy end states in monolayer Fe(Te,Se) high-temperature superconductors
- Condensation, excitation, pairing, and superfluid density in high- superconductors: magnetic resonance mode as a roton analogue and a possible spin-mediated pairing
- Dynamic interfacial polaron enhanced superconductivity of FeSe/SrTiO3
- Electronic Evidence of an Insulator-Superconductor Transition in Single-Layer FeSe/SrTiO3 Films
- Experimental Demonstration of the Sign Reversal of the Order Parameter in (Li1-xFex)OHFe1-yZnySe
- Band-edge BCS-BEC crossover in a two-band superconductor: physical properties and detection parameters
- Revealing the Empty-State Electronic Structure of Single-Unit-Cell FeSe/SrTiO
- Imaging gate-tunable Tomonaga-Luttinger liquids in 1H-MoSe mirror twin boundaries
- Identifying the `Fingerprint' of Antiferromagnetic Spin-Fluctuations on Iron-Pnictide Superconductivity
- Detection of bosonic mode as a signature of magnetic excitation in one unit cell FeSe on SrTiO3
- Superconducting parity effect across the Anderson limit
- Mott-driven BEC-BCS crossover in a doped spin liquid candidate, kappa-(BEDT-TTF)4Hg2.89Br8
- Heterostructural one-unit-cell FeSe/SrTiO3: from high-temperature superconductivity to topological states
- Real-space BCS-BEC crossover in FeSe monolayer
- Superconductivity of the FeSe/SrTiO3 Interface in the View of BCS-BEC Crossover
- Anisotropic gap structure and sign reversal symmetry in monolayer Fe(Se,Te)