NanoTechnology: Materials, Processes & Devices

Research that includes:

  • Development of nanostructure fabrication technology
  • Nanomagnetics, Microphotonics
  • CMOS Integrated Nanowires/Nanotubes (CMOS-Inn)

BPN971: High-Efficiency Ink-Based Mid-IR LEDs and Photodetectors

Theodorus Jonathan Wijaya
Hyong Kim
Naoki Higashitarumizu
Shu Wang
Kyuho Lee

Midwave infrared (MWIR) is significant for applications such as sensing, imaging, and spectroscopy. Traditional materials in this wavelength range, III-V and II-VI semiconductors, has poor performance due to their high Auger recombination rate and large dark currents. Due to the better properties of black phosphorus (BP) such as its low Auger recombination coefficient, BP-based mid-infrared light emitters and detectors have shown to outperform the state-of-the-art commercial devices. However, the scalability of these devices remains questionable because of the limitations of...

BPN947: High-Performance Mid-Infrared Optoelectronics

Shu Wang
Naoki Higashitarumizu
Shogo Tajima

Black phosphorus has emerged as a unique optoelectronic material, exhibiting tunable and high device performance from mid-infrared to visible wavelengths. Understanding the photophysics of this system is of interest to further advance device technologies based on it. Here we report the thickness dependence of the photoluminescence quantum yield at room temperature in black phosphorus while measuring the various radiative and non-radiative recombination rates. As the thickness decreases from bulk to ~4 nm, a drop in the photoluminescence quantum yield is initially observed due to enhanced...

BPN977: Metal-Loaded Metal Oxide Nanocomposites for Electronic Gas Sensors

Tzu-Chiao Wei
Yaprak Ozbakir
Veronica Arriaga
Sterling Cavanaugh
Carlo Carraro

Semiconducting metal oxides (MOX) such as SnO2 are an industry-standard material for chemiresistive sensing. However, many MOX-based gas sensors suffer from poor sensitivity, limited selectivity—particularly in the presence of water vapor—and insufficient stability. To address these shortcomings, catalytically active noble metals, such as Pd, are loaded onto the MOX materials to form noble metal-loaded MOX nanocomposites. In this work, we focus on Pd-loaded SnO2 (Pd/SnO2) due to their promising sensitivity to and selectivity for CO and CH4. Pd/SnO2 nanocomposites with varying Pd/Sn...

BPNX1001: Enhancing the Humidity Resistance of Chemiresistive Gas Sensors through Surface Functionalization (New Project)

Tzu Chiao Wei
Yaprak Ozbakir
HyoJun Min

Chemiresistive gas sensors based on semiconductor metal oxides, such as tin dioxide, help to identify and monitor toxic gases and pollution, and play a vital role in industrial and environmental applications. However, the interfering effect of ambient humidity is a major challenge in their reliable operation, as water molecules on the oxide surface can affect the sensitivity and other characteristics of the sensor. To address this challenge, several surface modifications are being explored in this project. In one approach, we are utilizing atomic layer deposition (ALD),...

BPN967: Quantum Emitters in Silicon Photonics

Lukasz Komza
Yu-Lung Tang
Hanbin Song
Zihuai Zhang

The G center, an atom-like single-photon emitter in silicon, has emerged as a promising candidate for realizing a quantum-coherent light source in integrated photonics. Our recent work demonstrating two-photon quantum interference with a single waveguide-integrated G center highlights the utility of G centers for photonic quantum information applications. However, improvements in the optical coherence properties of the G center must be achieved to enable its technological implementation. We will address this challenge by leveraging the integration capabilities of the silicon platform...

BPN931: Multiplexed Electroluminescent Device for Emission from Infrared to Ultraviolet Wavelength

Vivian Wang

Using electroluminescence as a metrology method could have many advantages for on-chip characterization of chemical composition, where the need for an on-chip light source can be eliminated and materials with different excitation energies can be characterized by the same device. However, the range of materials that can be used in electroluminescent devices is typically limited due to challenges related to material processing and band alignment. In this project, we aim to develop a multiplexed electroluminescent device that can produce electroluminescence from infrared to ultraviolet...

BPN982: Color-Tunable Alternating Current Light Emitting Diodes

Jongchan Kim
Vivian Wang

Alternating current (AC) driven light emitting devices (LEDs) are recently dragging attention due to its efficient color tunability. These devices consist of multilayer structure as the direct current (DC) driven LEDs, but the multilayer structure has drawbacks such as the large amount of material usage that increases the fabrication cost, and the difficult yield control due to a number of processing steps. In contrast, a recently demonstrated AC driven LED with a single contact has several advantages compared to the previous structures such as simple device structure, diverse...

BPN981: Suppressing Energy Losses in Compact Superconducting Qubits

Kadircan Godeneli
Mutasem Odeh
Eric Li

State-of-the-art quantum computers currently have qubit gate error rates that are too large for practical computing. Quantum error correction can protect computations from physical errors by encoding logical qubits in many physical qubits. However, physical qubit error rates need to be sufficiently low to minimize resource overhead and suppress errors. As a result, compact qubit designs with small dissipation and error rates are crucial to scaling up a fault-tolerant quantum computer. In this project, we aim to address the scaling up of superconducting quantum processors by...

Jordan L. Edmunds

Electrical Engineering and Computer Sciences
Professor Michel M. Maharbiz (Advisor)
Ph.D. 2022

BPN914: Elucidating Aging Mechanisms of Tin(IV) Oxide-based Gas Sensors

Isaac Zakaria
Yaprak Ozbakir
Veronica Arriaga
Steriling Cavanaugh

Despite decades of study and deployment, chemiresistive gas sensors based on SnO2 suffer from baseline drift due to aging of the SnO2 sensing material. In this work, we investigate how repeated, simulated operation of SnO2-based sensors causes irreversible changes in the electronic sensing behavior of SnO2, quantified through the bulk and inter-grain resistance of SnO2 as measured by potentiometric impedance spectroscopy (PIS). In tandem, we apply powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) to link the observed changes in the bulk and inter-grain...