Presentation
14 March 2018 Nanofiber nanoscopy and quantum noise limited biosensing (Conference Presentation)
Lars Madsen
Author Affiliations +
Abstract
Biology is a longstanding frontier for quantum metrology, where high optical intensities are frequently required to get sufficient signal, but lead to specimen damage [1]. In this regime quantum-noise limited sensitivity allows higher signal to noise or reduced optical intensities. I will give an overview of efforts in the Queensland Quantum Optics Laboratory to apply nanofiber based quantum-noise limited biosensor to biological measurements and our recent progress in nanofiber characterization. We demonstrate a quantum noise limited biosensor capable of detecting single unlabelled biomolecules with radii below 5 nm [2]. The nanoparticles are illuminated through a microscope objective and the scattered light is collected by a nanofiber. The collected light is detected with a heterodyne detector and obtains a quantum-noise limited performance down to 5 Hz and particle tracking with 1 kHz bandwidth. This detection performance opens for observation of biomolecular movements avoiding large biomarkers. We present a method for directly measuring the evanescent field of an optical nanofiber [3]. Unlike SEM-based methods, this method is non-destructive and yields a full profile of the nanofiber within minutes of fabrication. We obtain the radius with a resolution of 0.7 nm in 10 milliseconds. The method allows quality control and calibration of optical nanofibers for precision experiments for example as in the above mentioned biosensor. References [1] K. C. Neuman et al. Biophysics Journal 77, 2856-2863 (1999). [2] N. Mauranyapin, L. Madsen et al. Nature Photonics, in press July (2017) [3] L. Madsen, et al. Nano Letters, 16, 7333−7337 (2016)
Conference Presentation
© (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Lars Madsen "Nanofiber nanoscopy and quantum noise limited biosensing (Conference Presentation)", Proc. SPIE 10518, Laser Resonators, Microresonators, and Beam Control XX, 1051803 (14 March 2018); https://doi.org/10.1117/12.2287301
Advertisement
Advertisement
KEYWORDS
Nanofibers

Biosensors

Microresonators

Particles

Quantum optics

Sensors

Biology

Back to Top