Ultrafast response micropipette-based submicrometer thermocouple

TLDR

Thermocouples at sub‑micrometer scale are intrinsically suitable for scanned probe microscopies. Submicrometer‑size thermocouples were fabricated at the tip of gold‑coated glass micropipettes with a platinum core and tested. The devices exhibit sub‑microsecond response times, spatial selectivity below 2 µm along the pipette and 50 nm across, and successfully measured a focused argon‑ion laser beam, underscoring their promise as high‑resolution sensors.

Abstract

Submicrometer-size thermocouples at the tip of gold-coated glass micropipettes containing a platinum core were produced and tested. The response time of such thermocouples measured with different techniques appeared to be not bigger than a few microseconds. The calculations indicate that the spatial selectivity of this new class of thermocouple devices can be less than 2 μm along the pipette and less than 50 nm across the pipette. The suitability of this thermocouple for light intensity measurements with micrometer spatial resolution is demonstrated by measuring the focused beam of an argon-ion laser. In addition, such thermocouples are intrinsically suitable for applications in scanned probe microscopies. All these unique advantages make the pipette thermocouples a new and promising sensor in a variety of applications.