Definition of design guidelines, construction and performance of an ultra-stable scanning tunneling microscope for spectroscopic imaging

Abstract

Spectroscopic-imaging scanning tunneling microscopy is a powerful technique to study quantum materials, with the ability to provide information about the local electronic structure with subatomic resolution. However, as most spectroscopic measurements are conducted without feedback to the tip, it is extremely sensitive to vibrations coming from the environment. This requires the use of laboratories with low-vibration facilities combined with a very rigid microscope construction. In this article, we report on the design and fabrication of an ultra-stable STM for spectroscopic-imaging measurements that operates in ultra high vacuum and at low temperatures (4 K). We perform finite element analysis calculations for the main components of the microscope in order to guide design choices towards higher stiffness and we choose sapphire as the main material of the STM head. By combining these two strategies, we construct a STM head with measured lowest resonant frequencies above f0=13 kHz for the coarse approach mechanism, a value three times higher than previously reported, and in good agreement with the calculations. With this, we achieve an average vibration level of $\sim$ 6 fm/sqrt(Hz), without a dedicated low-vibration lab. We demonstrate the microscope's performance with topographic and spectroscopic measurements on the correlated metal Sr2RhO4, showing the quasiparticle interference pattern in real and reciprocal space with high signal-to-noise ratio.

References in corpus (10)

• Imaging the granular structure of high-Tc superconductivity in underdoped Bi2Sr2CaCu2O8+x
• Imaging the Effects of Individual Zinc Impurity Atoms on Superconductivity in Bi2Sr2CaCu2O8+delta
• An Intrinsic Bond-Centered Electronic Glass with Unidirectional Domains in Underdoped Cuprates
• Imaging Quasiparticle Interference in Bi2Sr2CaCu2O8+d
• Intra-unit-cell electronic nematicity of the high-Tc copper-oxide pseudogap states
• Interplay of magnetism and high-Tc superconductivity at individual Ni impurity atoms in Bi2Sr2CaCu2O8+d
• Anisotropic Energy Gaps of Iron-based Superconductivity from Intra-band Quasiparticle Interference in LiFeAs
• Fermi surface and quasiparticle excitations of Sr${}_2$RhO${}_4$
• Amplifier for scanning tunneling microscopy at MHz frequencies
• High chemical activity of a perovskite surface: reaction of CO with Sr${}_3$Ru${}_2$O${}_7$

Cited by in corpus (11)

• Vibration isolation with high thermal conductance for a cryogen-free dilution refrigerator
• Millikelvin scanning tunneling microscope at 20/22 T with a graphite enabled stick-slip approach and an energy resolution below 8$\mu$eV: Application to conductance quantization at 20 T in single atom point contacts of Al and Au
• Simplified feedback control system for Scanning Tunneling Microscopy
• Design and performance of an ultrahigh vacuum spectroscopic-imaging scanning tunneling microscope with a hybrid vibration isolation system
• Direct comparison of ARPES, STM, and quantum oscillation data for band structure determination in Sr${}_2$RhO${}_4$
• Nanofabricated tips for device-based scanning tunneling microscopy
• Design and characterization of a low-vibration laboratory with cylindrical inertia block geometry
• Removing background and estimating a unit height of atomic steps from a scanning probe microscopy image using a statistical model
• Dynamic bonding influenced by the proximity of adatoms to one-atom high step edges
• Quantum Weak Equivalence Principle and the Gravitational Casimir Effect in Superconductors
• Scanning Tunneling Microscopy in high vectorial magnetic fields