Bio


Asir Intisar Khan is a Ph.D. candidate in Electrical Engineering, Stanford University. His research focuses on the design, fabrication, and electro-thermal measurements of novel phase change superlattices and 2D heterostructures for high density, low-power memory both on the flexible and non-flexible platform. His research further expands into pushing these emerging memory technologies towards a novel and large design space for low-power brain-inspired computing. He is also interested in the prospect of these novel superlattices in thermoelectrics and energy harvesting.

Honors & Awards


  • Stanford Graduate Fellowship, Stanford University (2020 - 2023)
  • Departmental Fellowship, Electrical Engineering, Stanford University (2018-2019)

Education & Certifications


  • PhD Candidate, Stanford University, Electrical Engineering
  • M.Sc, Bangladesh University of Engineering and Technology, Electrical and Electronic Engineering (2018)
  • B.Sc, Bangladesh University of Engineering and Technology, Electrical and Electronic Engineering (2016)

Stanford Advisors


Personal Interests


Traveling, Cooking, Table Tennis

Current Research and Scholarly Interests


· Design, fabrication and characterization of superlattice-like Phase Change Memory (PCM) low power memory application: demonstrated ~8-10x reduction in the switching power compared to conventional PCM

· Interfacial thermoelectric engineering of PCM: Conceptualized and implemented the novel idea of incorporating interfacial thermoelectric heating in a conventional phase-change memory; Realization of ~2x reduction in the switching current density in conventional PCM using thermoelectric material

· Low power flexible nonvolatile memory: Fabrication and characterization of low power non-volatile memory on a flexible platform; achieved record-low switching current for flexible PCM to-date

· Low-power solid-state reflective display: Working on the optimization of low power solid-state reflective display using novel phase change heterostructures

As an aside, I have a general interest in quantum phenomena in nanostructures.

Lab Affiliations


All Publications


  • Modeling and computation of thermal and optical properties in silicene supported honeycomb bilayer and heterobilayer nanostructures MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING Noshin, M., Khan, A., Chakraborty, R., Subrina, S. 2021; 129
  • Uncovering Thermal and Electrical Properties of Sb2Te3/GeTe Superlattice Films. Nano letters Kwon, H., Khan, A. I., Perez, C., Asheghi, M., Pop, E., Goodson, K. E. 2021

    Abstract

    Superlattice-like phase change memory (SL-PCM) promises lower switching current than conventional PCM based on Ge2Sb2Te5 (GST); however, a fundamental understanding of SL-PCM requires detailed characterization of the interfaces within such an SL. Here we explore the electrical and thermal transport of SLs with deposited Sb2Te3 and GeTe alternating layers of various thicknesses. We find up to an approximately four-fold reduction of the effective cross-plane thermal conductivity of the SL stack (as-deposited polycrystalline) compared with polycrystalline GST (as-deposited amorphous and later annealed) due to the thermal interface resistances within the SL. Thermal measurements with varying periods of our SLs show a signature of phonon coherence with a transition from wave-like to particle-like phonon transport, further described by our modeling. Electrical resistivity measurements of such SLs reveal strong anisotropy (∼2000×) between the in-plane and cross-plane directions due to the weakly interacting van der Waals-like gaps. This work uncovers electrothermal transport in SLs based on Sb2Te3 and GeTe for the improved design of low-power PCM.

    View details for DOI 10.1021/acs.nanolett.1c00947

    View details for PubMedID 34270270

  • Two-Fold Reduction of Switching Current Density in Phase Change Memory Using Bi2Te3 Thermoelectric Interfacial Layer IEEE ELECTRON DEVICE LETTERS Khan, A., Kwon, H., Islam, R., Perez, C., Chen, M. E., Asheghi, M., Goodson, K. E., Wong, H., Pop, E. 2020; 41 (11): 1657–60
  • Large temperature coefficient of resistance in atomically thin two-dimensional semiconductors Applied Physics Letters Khan, A., Khakbaz, P., Brenner, K. A., Smithe, K., Mleczko, M. J., Esseni, D., Pop, E. 2020; 116 (20)

    View details for DOI 10.1063/5.0003312

  • Flexible Low-Power Superlattice-Like Phase Change Memory Khan, A., Daus, A., Pop, E., IEEE IEEE. 2020
  • Large Temperature Coefficient of Resistance in Atomically Thin 2D Devices IEEE Device Research Conference (DRC) Khan, A., Brenner, K., Smithe, K., Mleczko, M., Pop, E. 2019: 125–126
  • Thermal transport characterization of stanene/silicene heterobilayer and stanene bilayer nanostructures NANOTECHNOLOGY Noshin, M., Khan, A., Subrina, S. 2018; 29 (18): 185706

    Abstract

    Recently, stanene and silicene based nanostructures with low thermal conductivity have incited noteworthy interest due to their prospect in thermoelectrics. Aiming at the possibility of extracting lower thermal conductivity, in this study, we have proposed and modeled stanene/silicene heterobilayer nanoribbons, a new heterostructure and subsequently characterized their thermal transport by using an equilibrium molecular dynamics simulation. In addition, the thermal transport in bilayer stanene is also studied and compared. We have computed the thermal conductivity of the stanene/silicene and bilayer stanene nanostructures to characterize their thermal transport phenomena. The studied nanostructures show good thermal stability within the temperature range of 100-600 K. The room temperature thermal conductivities of pristine 10 nm × 3 nm stanene/silicene hetero-bilayer and stanene bilayer are estimated to be 3.63 ± 0.27 W m-1 K-1 and 1.31 ± 0.34 W m-1 K-1, respectively, which are smaller than that of silicene, graphene and some other 2D monolayers as well as heterobilayers such as stanene/graphene and silicene/graphene. In the temperature range of 100-600 K, the thermal conductivity of our studied bilayer nanoribbons decreases with an increase in the temperature. Furthermore, we have investigated the dependence of our estimated thermal conductivity on the size of the considered nanoribbons. The thermal conductivities of both the nanoribbons are found to increase with an increase in the width of the structure. The thermal conductivity shows a similar increasing trend with the increase in the ribbon length, as well. Our results suggest that, the low thermal conductivity of our studied bilayer structures can be further decreased by nanostructuring. The significantly low thermal conductivity of the stanene/silicene heterobilayer and stanene bilayer nanoribbons realized in our study would provide a good insight and encouragement into their appealing prospect in the thermoelectric applications.

    View details for PubMedID 29438099

  • Impact of tensile strain on the thermal transport of zigzag hexagonal boron nitride nanoribbon: An equilibrium molecular dynamics study MATERIALS RESEARCH EXPRESS Navid, I., Khan, A., Subrina, S. 2018; 5 (2)
  • Stanene-hexagonal boron nitride heterobilayer: Structure and characterization of electronic property SCIENTIFIC REPORTS Khan, A., Chakraborty, T., Acharjee, N., Subrina, S. 2017; 7
  • Thermal transport characterization of hexagonal boron nitride nanoribbons using molecular dynamics simulation AIP ADVANCES Khan, A., Navid, I., Noshin, M., Subrina, S. 2017; 7 (10)

    View details for DOI 10.1063/1.4997036

    View details for Web of Science ID 000414246100036

  • Characterization of thermal and mechanical properties of stanene nanoribbons: a molecular dynamics study RSC ADVANCES Khan, A., Paul, R., Subrina, S. 2017; 7 (80): 50485–95

    View details for DOI 10.1039/c7ra09209a

    View details for Web of Science ID 000414405800009

  • Stanene-hexagonal boron nitride heterobilayer: Structure and characterization of electronic property. Scientific reports Khan, A. I., Chakraborty, T. n., Acharjee, N. n., Subrina, S. n. 2017; 7 (1): 16347

    Abstract

    The structural and electronic properties of stanene/hexagonal boron nitride (Sn/h-BN) heterobilayer with different stacking patterns are studied using first principle calculations within the framework of density functional theory. The electronic band structure of different stacking patterns shows a direct band gap of ~30 meV at Dirac point and at the Fermi energy level with a Fermi velocity of ~0.53 × 106 ms-1. Linear Dirac dispersion relation is nearly preserved and the calculated small effective mass in the order of 0.05mo suggests high carrier mobility. Density of states and space charge distribution of the considered heterobilayer structure near the conduction and the valence bands show unsaturated π orbitals of stanene. This indicates that electronic carriers are expected to transport only through the stanene layer, thereby leaving the h-BN layer to be a good choice as a substrate for the heterostructure. We have also explored the modulation of the obtained band gap by changing the interlayer spacing between h-BN and Sn layer and by applying tensile biaxial strain to the heterostructure. A small increase in the band gap is observed with the increasing percentage of strain. Our results suggest that, Sn/h-BN heterostructure can be a potential candidate for Sn-based nanoelectronics and spintronic applications.

    View details for PubMedID 29180696

    View details for PubMedCentralID PMC5703857

  • Automatic Bengali Number Plate Reader Shahed, M., Udoy, M., Saha, B., Khan, A., Subrina, S., IEEE IEEE. 2017: 1364–68
  • Thermal Transport in Defected Armchair Graphene Nanoribbon: A Molecular Dynamics Study Noshin, M., Khan, A., Navid, I., Subrina, S., IEEE IEEE. 2017: 2600–2603
  • Thermal transport in graphene/stanene heterobilayer nanostructures with vacancies: an equilibrium molecular dynamics study RSC ADVANCES Khan, A., Paul, R., Subrina, S. 2017; 7 (71): 44780–87

    View details for DOI 10.1039/c7ra07843a

    View details for Web of Science ID 000411662100021

  • Impact of vacancies on the thermal conductivity of graphene nanoribbons: A molecular dynamics simulation study AIP ADVANCES Noshin, M., Khan, A., Navid, I., Uddin, H., Subrina, S. 2017; 7 (1)

    View details for DOI 10.1063/1.4974996

    View details for Web of Science ID 000395789900054

  • Bangla Voice Controlled Robot for Rescue Operation in Noisy Environment Bhattacharjee, A., Khan, A., Haider, M. Z., Fattah, S. A., Chowdhury, D., Sarkar, M., Shahnaz, C., IEEE IEEE. 2016: 3284–88
  • Equilibrium Molecular Dynamics (MD) Simulation Study of Thermal Conductivity of Graphene Nanoribbon: A Comparative Study on MD Potentials ELECTRONICS Khan, A., Navid, I., Noshin, M., Uddin, H., Hossain, F., Subrina, S. 2015; 4 (4): 1109–24