Perspectives on deterministic control of quantum point defects by scanned probes

Control over individual point defects in solid-state systems is becoming increasingly important, not only for current semiconductor industries but also for next generation quantum information science and technologies. To realize the potential of these defects for scalable and high-performance quantum applications, precise placement of defects and defect clusters at the nanoscale is required, along with improved control over the nanoscale local environment to minimize decoherence. These requirements are met using scanned probe microscopy in silicon and III-V semiconductors, which suggests the extension to hosts for quantum point defects such as diamond, silicon carbide, and hexagonal boron nitride is feasible. Here we provide a perspective on the principal challenges toward this end, and new opportunities afforded by the integration of scanned probes with optical and magnetic resonance techniques.

Measurements of trapped-ion heating rates with exchangeable surfaces in close proximity

ABSTRACTElectric-field noise from the surfaces of ion-trap electrodes couples to the ion’s charge causing heating of the ion’s motional modes. This heating limits the fidelity of quantum gates implemented in quantum information processing experiments. The exact mechanism that gives rise to electric-field noise from surfaces is not well-understood and remains an active area of research. In this work, we detail experiments intended to measure ion motional heating rates with exchangeable surfaces positioned in close proximity to the ion, as a sensor to electric-field noise. We have prepared samples with various surface conditions, characterized in situ with scanned probe microscopy and electron spectroscopy, ranging in degrees of cleanliness and structural order. The heating-rate data, however, show no significant differences between the disparate surfaces that were probed. These results suggest that the driving mechanism for electric-field noise from surfaces is due to more than just thermal excitations alone.

On-line Scanned Probe Microscopy Transparently Integrated with Dual Beam SEM/FIB Systems

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Eliminate Optical Microscopy

This special issue of Microscopy Today is devoted to light microscopy. Light microscopy is microscopy that employs light as a medium, or so I thought. Every week I see “optical microscopy” used as a synonym for light microscopy. I cannot understand the popularity of this confusing term. For people outside our field, the term “optical microscopy” must be perplexing: does it mean electron optical or light optical? My point is that we should present the techniques we use in clear unambiguous language: light microscopy, electron microscopy, scanned probe microscopy, etc. Regardless of logic, there are still strong adherents to the term “optical microscopy.”

On-Line Scanned Probe Microscopy Transparently Integrated with Twin SEM/FIB Systems

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

AFM Measurements of DNA Molecule Electron Transport Properties

Deoxyribonucleic acid (DNA) has been considered as a possibility for molecular electronics. Because DNA is able to recognize other molecules—other strands of DNA—and because it binds together with similar DNA strands in a very unique way, scientists have suggested the possibility of using DNA as an electronic circuit without having to build in any other circuitry. The DNA would bind with other similar DNA strands that it recognizes and then use the connecting properties of the DNA to create a self-assembled biological wire for electrical conduction. Until recently, uncertainty existed about whether DNA could conduct at all, and if it could, how well it could conduct. Scientific speculations ranged from DNA being a superconductor to a complete insulator. Recent research, however, by Dr. Sidney R. Cohen in collaboration with Dr. Ron Naaman and Dr. Claude Nogues of the Weizmann Institute of Science, Scanned Probe Microscopy Unit, in Rehovot, Israel, aided by the enabling technologies of ultra-high-resolution microscopy and negative-stiffness vibration isolation, has shed new light on the electrical transport properties of DNA, focusing on the capacity of single molecules of DNA to transport current along individual strands.