Electroactive micro and nanowells for optofluidic storage

Bernardo Cordovez,Demetri Psaltis,David Erickson

doi:10.1364/oe.17.021134

Abstract

This paper reports an optofluidic architecture which enables reversible trapping, detection and long term storage of spectrally multiplexed semiconductor quantum dot cocktails in electrokinetically active wells ranging in size from 200nm to 5microm. Here we describe the microfluidic delivery of these cocktails, fabrication method and principal of operation for the wells, and characterize the readout capabilities, storage and erasure speeds, internal spatial signal uniformity and potential storage density of the devices. We report storage and erase speeds of less than 153ms and 30ms respectively and the ability to provide 6-bit storage in a single 200nm well through spectral and intensity multiplexing. Furthermore, we present a novel method for enabling passive long term storage of the quantum dots in the wells by transporting them through an agarose gel matrix. We envision that this technique could find eventual application in fluidic memory or display devices.

Highlights

Recent advances in micro- and nano-fluidics has rekindled an interest in fluid based optoelectronic [1] devices
Several fluidic data storage and logic devices have been recently demonstrated, including that by Thorsen et al [2] where a microfluidic device was used to create an array of discrete chambers which could be probed for the presence of a dye, that by Groisman et al [3] which exploited viscoelastic polymer solutions to create fluidic flip-flops, and that by Prakash et al [4] in which microfluidic bubbles where used to generate an array of universal Boolean logic components
We present a novel method for enabling passive long term nonvolatile of the quantum dots packets by storing them in wells containing an agarose gel matrix

Summary

Introduction

Recent advances in micro- and nano-fluidics has rekindled an interest in fluid based optoelectronic [1] devices Within this larger field, several fluidic data storage and logic devices have been recently demonstrated, including that by Thorsen et al [2] where a microfluidic device was used to create an array of discrete chambers which could be probed for the presence of a dye, that by Groisman et al [3] which exploited viscoelastic polymer solutions to create fluidic flip-flops, and that by Prakash et al [4] in which microfluidic bubbles where used to generate an array of universal Boolean logic components.

Principle of Operation

Device Temporal Characterization and Well Spatial Density Analysis

Non-Volatile Storage Using an Agarose Gel Matrix

Outlook and Conclusions

Findings

Electroactive Nano and Microwell Fabrication