Using Quantum Confinement to Uniquely Identify Devices

Abstract

Modern technology unintentionally provides resources that enable the trust of everyday interactions to be undermined. Some authentication schemes address this issue using devices that give a unique output in response to a challenge. These signatures are generated by hard-to-predict physical responses derived from structural characteristics, which lend themselves to two different architectures, known as unique objects (UNOs) and physically unclonable functions (PUFs). The classical design of UNOs and PUFs limits their size and, in some cases, their security. Here we show that quantum confinement lends itself to the provision of unique identities at the nanoscale, by using fluctuations in tunnelling measurements through quantum wells in resonant tunnelling diodes (RTDs). This provides an uncomplicated measurement of identity without conventional resource limitations whilst providing robust security. The confined energy levels are highly sensitive to the specific nanostructure within each RTD, resulting in a distinct tunnelling spectrum for every device, as they contain a unique and unpredictable structure that is presently impossible to clone. This new class of authentication device operates with minimal resources in simple electronic structures above room temperature.

Resonant-Tunnelling Diodes as PUF Building Blocks

“…RTDs, simple electronic structures utilising quantum confinement, have been proposed as building blocks for PUFs [3]. The RTD encapsulates a quantum nanostructure between two electrical contacts and displays an exotic I-V characteristic not seen in classical devices.…”

“…The general design of RTDs was shown in [3]. Our previous work focuses on the physical properties of the RTDs.…”

Editor’s choice: recent research highlights from the International Journal of Nanomedicine

“…2016;11:3265-3276. Nanomedicine 1 has increasingly received a tremendous attention over the past two decades as a potential multidimensional field, developing nano-applications that are transforming a host of medical products and services, 2,3 including drug delivery 4 and health-monitoring devices, and the possibility of gaining new insights about "undruggable targets" and treatment through atomic-scale precision is increasing rapidly. 5 Although it is uncertain as to which of the new delivery platforms will become the most effective and useful, it is certain that many new approaches will be investigated in the years to come.…”

“…Notably, outstanding QD photostability proves essential for robust image acquisition and quantitative analysis of staining intensity, which is otherwise a fundamental limitation of other organic molecular probes. 2,25 Such advances in QD synthesis and surface nanofabrications achieved during the last decade have produced multicolor QD-antibody conjugates aiming to expand multiplexing capabilities of immunofluorescence staining, offering exciting opportunities in gene expression studies.…”

N-state random switching based on quantum tunnelling

“…The sudden current drop occurring between the two conduction regimes shows as a narrow resonance in the I-V characteristics. The bistability 19 and fast switching characteristics 20 emerging from the sharp NDR resonance of RTDs makes them promising candidates for applications in multi-valued logic circuits 21 , random-access memories 22 , multi-function logic gates 23 , chaotic signal generation 3,24,25 , single-photon switching 26 , unique device identification 27 and terahertz oscillators 28,29 . Due to their N-shaped NDR characteristics, the RTD's current is a single-valued function of voltage whereas the opposite is not true, as current values between those of the peak (I p ) and the valley (I v ) exhibit multiple voltage levels due to the different aforementioned conduction mechanisms.…”