---
OA_type: closed access
_id: '22819'
abstract:
- lang: eng
  text: Bio-inspired photonic synapses integrate optical sensing, memory, and processing
    in a single platform, overcoming the bottlenecks of traditional CMOS-based vision
    sensors. Most existing neuromorphic vision systems either rely on electrical inputs
    for bidirectional conductance modulation, limiting their operating speed and bandwidth,
    or lack nonvolatility, leading to nonlinear weight updates and poor efficiency
    in image recognition tasks. Here, we report a two-terminal, fully light-controlled
    synaptic memristor based on CsPbBr3/ZnO nanorod heterojunction that demonstrates
    4-bit memory storage and optical logic operations within a single architecture.
    The device emulates essential functions of both excitatory and inhibitory synapses,
    utilizing positive photoconductivity under UV illumination (λ = 375 nm) and anomalous
    negative photoconductivity under visible light (λ = 450 nm). By controlling defect
    concentrations at the CsPbBr3/ZnO nanorod interface, the device exhibits nonvolatile
    multibit memory with near-linear, symmetric conductance modulation, achieving
    92.4% image recognition accuracy with a convolutional neural network. The bidirectional
    photoresponse enables reconfigurable optical logic operations, demonstrating integrated
    logic-in-memory. Additionally, when integrated on a flexible platform, the device
    demonstrates stable synaptic performance under repeated mechanical bending. These
    results highlight the potential of CsPbBr3/ZnO nanorod heterojunction-based all-photonic
    synapses as building blocks for multibit storage, optical information processing,
    and wearable neuromorphic vision systems.
acknowledgement: SS sincerely acknowledges the fellowship received from the Ministryof
  Education, Government of India, to carry out this research. SKRacknowledges the
  financial support from DST Nano-mission (Projectno. DST/NM/TUE/QM8 2019G 5). The
  authors also thank the CentralResearch Facility (CRF) at IIT Kharagpur for providing
  the characteriza-tion tools.
article_number: e75437
article_processing_charge: No
author:
- first_name: Subham
  full_name: Saha, Subham
  last_name: Saha
- first_name: Shreyasi
  full_name: Das, Shreyasi
  id: c102f9d5-4f26-11ef-94d5-9047d2a9105b
  last_name: Das
- first_name: Baidyanath
  full_name: Roy, Baidyanath
  last_name: Roy
- first_name: Santu Kumar
  full_name: Ghosh, Santu Kumar
  last_name: Ghosh
- first_name: Rohit
  full_name: Satpathy, Rohit
  last_name: Satpathy
- first_name: James
  full_name: Bullock, James
  last_name: Bullock
- first_name: Ranjith R.
  full_name: Unnithan, Ranjith R.
  last_name: Unnithan
- first_name: Samit K.
  full_name: Ray, Samit K.
  last_name: Ray
citation:
  ama: Saha S, Das S, Roy B, et al. Interface engineered perovskite-oxide heterojunction
    all-photonic synapses for multibit memory, optical logic, and wearable neuromorphic
    vision. <i>Small</i>. 2026. doi:<a href="https://doi.org/10.1002/smll.75437">10.1002/smll.75437</a>
  apa: Saha, S., Das, S., Roy, B., Ghosh, S. K., Satpathy, R., Bullock, J., … Ray,
    S. K. (2026). Interface engineered perovskite-oxide heterojunction all-photonic
    synapses for multibit memory, optical logic, and wearable neuromorphic vision.
    <i>Small</i>. Wiley. <a href="https://doi.org/10.1002/smll.75437">https://doi.org/10.1002/smll.75437</a>
  chicago: Saha, Subham, Shreyasi Das, Baidyanath Roy, Santu Kumar Ghosh, Rohit Satpathy,
    James Bullock, Ranjith R. Unnithan, and Samit K. Ray. “Interface Engineered Perovskite-Oxide
    Heterojunction All-Photonic Synapses for Multibit Memory, Optical Logic, and Wearable
    Neuromorphic Vision.” <i>Small</i>. Wiley, 2026. <a href="https://doi.org/10.1002/smll.75437">https://doi.org/10.1002/smll.75437</a>.
  ieee: S. Saha <i>et al.</i>, “Interface engineered perovskite-oxide heterojunction
    all-photonic synapses for multibit memory, optical logic, and wearable neuromorphic
    vision,” <i>Small</i>. Wiley, 2026.
  ista: Saha S, Das S, Roy B, Ghosh SK, Satpathy R, Bullock J, Unnithan RR, Ray SK.
    2026. Interface engineered perovskite-oxide heterojunction all-photonic synapses
    for multibit memory, optical logic, and wearable neuromorphic vision. Small.,
    e75437.
  mla: Saha, Subham, et al. “Interface Engineered Perovskite-Oxide Heterojunction
    All-Photonic Synapses for Multibit Memory, Optical Logic, and Wearable Neuromorphic
    Vision.” <i>Small</i>, e75437, Wiley, 2026, doi:<a href="https://doi.org/10.1002/smll.75437">10.1002/smll.75437</a>.
  short: S. Saha, S. Das, B. Roy, S.K. Ghosh, R. Satpathy, J. Bullock, R.R. Unnithan,
    S.K. Ray, Small (2026).
das_tickbox: '1'
dataavailabilitystatement: The data that support the findings of this study are available
  in theSupporting Information of this article.
date_created: 2026-09-06T22:01:58Z
date_published: 2026-08-25T00:00:00Z
date_updated: 2026-09-09T13:40:30Z
day: '25'
department:
- _id: HrPo
doi: 10.1002/smll.75437
external_id:
  pmid:
  - '42643004'
fulldoi: https://doi.org/10.1002/smll.75437
keyword:
- all-optical synapse
- bidirectional photoresponse
- defect engineering
- flexible neuromorphic vision
- multibit nonvolatile memory
- negativephotoconductivity
- optical logic gate
language:
- iso: eng
month: '08'
oa_version: None
pmid: 1
publication: Small
publication_identifier:
  eissn:
  - 1613-6829
  issn:
  - 1613-6810
publication_status: epub_ahead
publisher: Wiley
quality_controlled: '1'
researchdata_availability: no
scopus_import: '1'
status: public
supplementarymaterial: yes
title: Interface engineered perovskite-oxide heterojunction all-photonic synapses
  for multibit memory, optical logic, and wearable neuromorphic vision
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2026'
...