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Rapid Voltage Sensing with Single Nanorods via the Quantum Confined Stark Effect.

ABSTRACT: Properly designed colloidal semiconductor quantum dots (QDs) have already been shown to exhibit high sensitivity to external electric fields via the quantum confined Stark effect (QCSE). Yet, detection of the characteristic spectral shifts associated with the effect of the QCSE has traditionally been painstakingly slow, dramatically limiting the sensitivity of these QD sensors to fast transients. We experimentally demonstrate a new detection scheme designed to achieve shot-noise-limited sensitivity to emission wavelength shifts in QDs, showing feasibility for their use as local electric field sensors on the millisecond time scale. This regime of operation is already potentially suitable for detection of single action potentials in neurons at a high spatial resolution.

SUBMITTER: Bar-Elli O

PROVIDER: S-EPMC6053642 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Rapid Voltage Sensing with Single Nanorods via the Quantum Confined Stark Effect.

Bar-Elli Omri O Steinitz Dan D Yang Gaoling G Tenne Ron R Ludwig Anastasia A Kuo Yung Y Triller Antoine A Weiss Shimon S Oron Dan D

ACS photonics 20180624 7

Properly designed colloidal semiconductor quantum dots (QDs) have already been shown to exhibit high sensitivity to external electric fields via the quantum confined Stark effect (QCSE). Yet, detection of the characteristic spectral shifts associated with the effect of the QCSE has traditionally been painstakingly slow, dramatically limiting the sensitivity of these QD sensors to fast transients. We experimentally demonstrate a new detection scheme designed to achieve shot-noise-limited sensitiv ...[more]

PMID: 30042952

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