Publications by Teodor Rosca | EPFL Graph Search

Millimeter-wave to near-terahertz sensors based on reversible insulator-to-metal transition in VO2

Mihai Adrian Ionescu, Teodor Rosca, Fatemeh Qaderi Rahaqi

In the quest for low power bio-inspired spiking sensors, functional oxides like vanadium dioxide are expected to enable future energy efficient sensing. Here, we report uncooled millimeter-wave spiking detectors based on the sensitivity of insulator-to-met ...

SPRINGERNATURE2023

Static and Dynamic Stochastic Analysis of a Temperature-Sensitive VO2 Spiking Neuron

Mihai Adrian Ionescu, Teodor Rosca

In this work, we investigate the intrinsic cycle-to-cycle variations in a spiking temperature-sensitive neuron, based on the resistive switching of a Vanadium dioxide (VO2) two-terminal device. We study how this phenomenon impacts the spike rate jitter, an ...

IEEE2023

Energy Efficient Sensing using Steep Slope Devices

Teodor Rosca

Today, we are witnessing the Internet of Things (IoT) revolution, which facilitates and improves our lives in many aspects, but comes with several challenges related to the technology deployment at large scales. Handling ever growing amounts of information ...

EPFL2022

Spike-Based Sensing and Communication for Highly Energy-Efficient Sensor Edge Nodes

Mihai Adrian Ionescu, Teodor Rosca

Highly energy-efficient wireless sensor nodes are a prerequisite for a sustainable operation of the Internet of things. Therefore, classical approaches for system design based on digital signal processing are not a viable solution, but system design has to ...

IEEE2022

Intrinsic switching in Si-doped HfO2: A study of Curie-Weiss law and its implications for negative capacitance field-effect transistor

Mihai Adrian Ionescu, Igor Stolichnov, Ali Saeidi, Teodor Rosca, Eamon Patrick O'Connor, Matteo Cavalieri, Carlotta Gastaldi, Sadegh Kamaei Bahmaei

HfO2-based ferroelectrics are considered a promising class of materials for logic and memory applications due to their CMOS compatibility and ferroelectric figures of merit. A steep-slope field-effect-transistor (FET) switch is a device for logic applicati ...

AMER INST PHYSICS2021

High Tuning Range Spiking 1R-1T VO2 Voltage-Controlled Oscillator for Integrated RF and Optical Sensing

Mihai Adrian Ionescu, Teodor Rosca, Fatemeh Qaderi Rahaqi

In this work we propose and experimentally validate a relaxation spiking oscillator architecture with ultra-high tuning range (higher than 400%, from 5KHz to more than 25kHz when the control voltage is varied from 2.5 to 5V) that exploits the reversible me ...

IEEE2021

High Tuning Range Spiking 1R-1T VO2 Voltage-Controlled Oscillator for Integrated RF and Optical Sensing

Mihai Adrian Ionescu, Teodor Rosca, Fatemeh Qaderi Rahaqi

In this work we propose and experimentally validate a relaxation spiking oscillator architecture with ultra-high tuning range (higher than 400%, from 5KHz to more than 25kHz when the control voltage is varied from 2.5 to 5V) that exploits the reversible me ...

IEEE2021

An Experimental Study Of The Photoresponse Of 1T-1R Oscillators Based On Vanadium Dioxide: Towards Spiking Sensing Systems

Olivier Martin, Mihai Adrian Ionescu, Teodor Rosca, Marco Riccardi, Fatemeh Qaderi Rahaqi

In this work we investigate the effect of visible light radiation on compact 1T-1R relaxation spiking oscillator cells based on 2-terminal Vanadium dioxide (VO2) structures. We illuminate the devices using a tunable wavelength laser between 400 and 850 nm ...

IEEE2021

Gate energy efficiency and negative capacitance in ferroelectric 2D/2D TFET from cryogenic to high temperatures

Mihai Adrian Ionescu, Ali Saeidi, Teodor Rosca, Matteo Cavalieri, Carlotta Gastaldi, Luca Capua, Sadegh Kamaei Bahmaei

We report the fabrication process and performance characterization of a fully integrated ferroelectric gate stack in a WSe2/SnSe2 Tunnel FETs (TFETs). The energy behavior of the gate stack during charging and discharging, together with the energy loss of a ...

NATURE PORTFOLIO2021

Nanowire Tunnel FET with Simultaneously Reduced Subthermionic Subthreshold Swing and Off-Current due to Negative Capacitance and Voltage Pinning Effects

Mihai Adrian Ionescu, Igor Stolichnov, Ali Saeidi, Teodor Rosca, Matteo Cavalieri

Nanowire tunnel field-effect transistors (TFETs) have been proposed as the most advanced one-dimensional (1D) devices that break the thermionic 60 mV/decade of the subthreshold swing (SS) of metal oxide semiconductor field-effect transistors (MOSFETs) by u ...

AMER CHEMICAL SOC2020