About

Evelyn Hu is the Tarr-Coyne Professor of Applied Physics and of Electrical Engineering at Harvard University, affiliated with the Harvard John A. Paulson School of Engineering and Applied Sciences. She is a participant in the Nanoscale Science and Engineering Center and specializes in applied physics, materials, photonics, quantum engineering, electrical engineering, and science, technology, innovation, and public policy. Her research focuses on nanoscience and nanomaterials, with notable contributions recognized by awards such as the American Physical Society Honor Dresselhaus Prize. She has been involved in advancing quantum research, including developing platforms to probe and control qubits in silicon for quantum networks. Her work is influential in the fields of surface and interface science, and she is actively engaged in science and engineering education.

Research topics

• Computer Science
• Physics
• Engineering physics
• Electrical engineering
• Telecommunications
• Quantum mechanics
• Engineering

Selected publications

• Built‐In Electric Field Enhanced Sodium Storage in Fe₃O₄/Fe Homogeneous Heterojunction Confined by N‐Doped Carbon Shells

  Small · 2025-08-18

  article

  Abstract Iron oxide (Fe 3 O 4 ) has attracted significant attention as a promising anode material for sodium‐ion batteries (SIBs) due to its natural abundance, environmental benignity, and high theoretical capacity of 926 mA h g −1 . Nevertheless, its practical application is limited by intrinsic drawbacks, including low electrical conductivity, sluggish Na⁺ diffusion kinetics, and severe volume variation during cycling, leading to rapid capacity fading and poor rate capability. To address these issues, a novel Fe 3 O 4 /Fe@N‐doped carbon (Fe 3 O 4 /Fe@CN) nanostructure is rationally designed, which integrates Fe 3 O 4 /Fe homogeneous heterojunctions with a uniform nitrogen‐doped carbon shell. The built‐in electric field at the Fe‐Fe 3 O 4 interface promotes charge redistribution and accelerates electron/ion transport, while the N‐doped carbon shell enhances electrical conductivity and buffers mechanical stress during sodiation/desodiation processes. Benefiting from this synergistic structure, the Fe 3 O 4 /Fe@CN anode delivers a high reversible capacity of 336.9 mA h g −1 at 0.1 A g −1 , excellent rate capability with 244.7 mA h g −1 at 2 A g −1 , and remarkable cycling stability, retaining 76.4% capacity after 500 cycles. Furthermore, a full cell assembled with a Na 3 V 2 (PO 4 ) 3 cathode exhibits a high energy density of 112.67 Wh·kg −1 at 51.42 W·kg −1 and outstanding cycling performance. This study offers a versatile strategy to unlock the potential of Fe 3 O 4 for high‐performance SIB anodes through heterojunction and interfacial engineering.

  PublisherDOI

• Selective Undercut of Undoped Optical Membranes for Spin-Active Color Centers in 4H- Silicon Carbide

  ACS Nano · 2025-01-29 · 8 citations

  articleOpen accessSenior author

  Silicon carbide (SiC) is a semiconductor used in quantum information processing, microelectromechanical systems, photonics, power electronics, and harsh environment sensors. However, its high-temperature stability, high breakdown voltage, wide bandgap, and high mechanical strength are accompanied by a chemical inertness, which makes complex micromachining difficult. Photoelectrochemical (PEC) etching is a simple, rapid means of wet processing SiC, including the use of dopant-selective etch stops that take advantage of the mature SiC homoepitaxy. However, dopant-selective PEC etching typically relies on highly doped material, which poses challenges for device applications such as quantum defects and photonics that benefit from low doping to produce robust emitter properties and high optical transparency. In this work, we develop a selective PEC process that relies not on high doping but on the electrical depletion of a fabricated diode structure, allowing the selective etching of an n-doped substrate wafer versus an undoped epitaxial (carrier density of 1(10)14 cm–3) device layer. We characterize the photoresponse and PEC behavior of the diode under bias and use those insights to suspend large (100 × 100 μm) undoped membranes of SiC. We further characterize the compatibility of membranes with quantum emitters, performing comparative spin spectroscopy between undoped and highly doped membrane structures, finding the use of undoped material improves ensemble spin lifetime by >5×. This work enables the fabrication of high-purity suspended thin films suitable for scalable photonics, mechanics, and quantum technologies in SiC.

  PublisherDOI

• Microfluidic heat sinks enhanced with a 2D metal framework for flexible thermal management

  SSRN Electronic Journal · 2025-01-01

  preprintOpen access
  PublisherDOI

• Prediction model for severe autoimmune encephalitis: a tool for risk assessment and individualized treatment guidance

  Frontiers in Neurology · 2025-03-18

  articleOpen access

  Background: Severe autoimmune encephalitis (AE) can cause significant neurological deficits, status epilepticus, status dystonicus, and even death, which can be life-threatening to patients. Accurate risk stratification for severe AE progression is critical for optimizing therapeutic strategies. The comprehensive prediction models for severe AE based on routine clinical data and laboratory indicators remain lacking. Objective: To develop and validate a prediction model for severe AE to optimize individualized treatment. Methods: We collected clinical data and laboratory examination results from 207 patients with confirmed AE. The study population was divided into development and validation cohort. A prediction model for severe AE was constructed using a nomogram and was rigorously validated both internally and externally. Severe AE was defined as modified Rankin Scale (mRS) > 2 and Clinical Assessment Scale for Encephalitis (CASE) > 4. Results: The variables ultimately included in the nomogram for the severe AE predictive model were age, psychiatric and/or behavioral abnormalities, seizures, decreased level of consciousness, cognitive impairment, involuntary movements, autonomic dysfunction, and increased intrathecal IgG synthesis rate. It demonstrated excellent discriminative capacity and calibration through internal-external validation. Conclusion: The prediction model has highly feasibility in clinical practice, and holds promise as an important tool for risk assessment and guiding individualized treatment in patients with AE.

  PublisherOA PDFDOI

• Probing negative differential resistance in silicon with a P-I-N diode-integrated T center ensemble

  ArXiv.org · 2025-01-21 · 1 citations

  preprintOpen accessSenior author

  Solid-state defect quantum systems are exquisite probes of their local charge environment. Nonlinear dynamical electric fields in solids are challenging to characterize directly, conventionally limited to coarse macroscopic methods which fail to capture subtle effects in the material. Here, through transient optical spectroscopy on an embedded T center ensemble, we realize the in-situ observation of a silicon PIN-diode phase transition to a regime of self-sustained carrier oscillatory dynamics characteristic of negative differential resistance. Manifest in both the ensemble electroluminescence and photoluminescence, we find a temperature and field-dependent phase space for persistent undamped amplitude oscillations indicative of a collective ensemble response to the field dynamics. These findings shed new light on the cryogenic behavior of silicon, provide fundamental insight into the physics of the T center for improved quantum device performance, and open a promising new direction for defect-based local quantum sensing in semiconductor devices.

  PublisherOA PDFDOI

• A Suspended 4H-Silicon Carbide Membrane Platform for Defect Integration into Quantum Devices

  Nano Letters · 2025-10-15 · 2 citations

  articleSenior author

  4H-silicon carbide is a promising platform for solid-state quantum technology due to its commercial availability as a wide bandgap semiconductor and ability to host numerous spin-active color centers. Integrating color centers into suspended nanodevices enhances defect control and readout, key advances needed to fully harness their potential. However, challenges in developing robust fabrication processes for 4H-SiC thin films, due to the material's chemical and mechanical stability, limit their implementation in quantum applications. Here, we report on a new fabrication approach that first synthesizes suspended thin films from a monolithic platform and then patterns devices. With this technique, we fabricate and characterize structures tailored for defect integration, demonstrating 1D photonic crystal cavities, with and without waveguide interfaces, and lithium niobate on 4H-SiC acoustic cavities. This approach allows for greater fabrication flexibility, supporting high temperature annealing and heterogeneous material platform compatibility, providing a versatile platform for scalable fabrication of 4H-SiC devices for quantum technologies.

  PublisherDOI

• Erratum: Three-Dimensional Reconfigurable Optical Singularities in Bilayer Photonic Crystals [Phys. Rev. Lett. <b>132</b>, 073804 (2024)]

  Physical Review Letters · 2025-05-28 · 1 citations

  erratumOpen access

  In the original Letter, the value for the thickness of each slab was mistakenly reported as 0.54a; the correct value is 0.35a.

  PublisherOA PDFDOI

• Interface-mediated dc electro-optic instability in lithium niobate nanophotonics

  Research Square · 2025-01-21 · 4 citations

  preprintOpen access
  PublisherOA PDFDOI

• Design and Performance of a 3D-Printed Vertical Axis Wind Turbine

  2025-07-16 · 1 citations

  article

  This study investigates the design and performance of a Vertical Axis Wind Turbine (VAWT), which uses the S809 airfoil for blade design and employs 3D printing for blade fabrication. Performance testing is conducted in a Low-Speed Wind Tunnel (LSWT) to evaluate the turbine’s power output under varying rotational speeds. Experimental results show a wind speed of 9.51 m/s, the maximum power output of the generator reached 450 mW. Therefore, 3D printing has the potential to develop wind turbine components for renewable energy technology.

  PublisherDOI

• Stack-related electron reconstruction induces in-plane softening in twisted bilayer graphene

  Carbon · 2025-07-02 · 1 citations

  article
  PublisherDOI

Recent grants

• EAGER: Deterministic Placement of Qubits in Cavities for Strongly Coupled Quantum Repeaters

  NSF · $300k · 2017–2020

• Materials World Network to Optimize the Growth of InGaN Quantum Dots within High Quality Optical Micro-Cavities

  NSF · $546k · 2010–2013

Frequent coauthors

• John E. Bowers

  101 shared

• Steven P. DenBaars

  61 shared

• Ataç İmamoğlu

  ETH Zurich

  40 shared

• K. Hennessy

  39 shared

• D.I. Babic

  University of Zagreb

  37 shared

• Umesh K. Mishra

  37 shared

• Richard P. Mirin

  National Institute of Standards and Technology

  35 shared

• Yating Wan

  King Abdullah University of Science and Technology

  34 shared

Labs

• Hu Research GroupPI

Awards & honors

• Dresselhaus Prize