ASSISTANT PROFESSOR
(Glenn and Susanne Culler Endowed Chair)
1119 Harold Frank Hall,
Department of Computer Science,
University of California, Santa Barbara
Email: prabhanjan at cs ucsb edu
I'm an assistant professor in the department of computer science at UCSB.
I graduated with a Ph.D. (2013 - 2017) from UCLA under the supervision of Amit Sahai and Rafail Ostrovsky. I spent two years (2017 - 2019) as a postdoc at CSAIL, MIT under the supervision of Vinod Vaikuntanathan.
I'm broadly interested in all aspects of cryptography and specifically, I'm interested in (post-)quantum cryptography.
CURRENT STUDENTS
Ph.D.:
Divyanshu Bhardwaj
PAST STUDENTS
Ph.D.:
Fatih Kaleoglu (first job after graduation: Global Technology Applied Research at JPMorgan Chase)
Undergraduate:
Zikuan Huang (Tsinghua University)
Siyuan Chen (Tsinghua University)
Zihan Hu (BS, Tsinghua University -> Ph.D. student at EPFL)
Manu Kondapaneni (BS, UCSB -> Ph.D. student at Northeastern University)
Aditya Gulati (BS, IIT Kanpur -> Ph.D. student at UCSB)
Zackary Glazewski (BS, UCSB)
Rowan-James Tran (BS, UCSB)
Aashay Parab (BS, UCSB)
Anika Arora (BS, UCSB)
Mohit Sharma (IIT Roorkee)
Philip Axelrod (BS, UCSB)
Masters:
Hrishikesh Saikia (MS, Chennai Mathematical Institute)
Saikumar Yadugiri (MS, UCSB -> Ph.D. student at University of Wisconsin Madison)
(Note: Only published research papers with proceedings are numbered below.)
2025
61. Revocable Encryption, Programs, and More: The Case of Multi-Copy Security
(with Saachi Mutreja, Alexander Poremba)
ITC 2025
60. Pseudorandom Unitaries in the Haar Random Oracle Model
(with John Bostanci, Aditya Gulati, Yao-Ting Lin)
CRYPTO 2025
(with Omar Alrabiah, Miranda Christ, Yevgeniy Dodis, Sam Gunn)
STOC 2025
(Invited to the SICOMP Special Issue for STOC'25)
58. Pseudorandomness in the (Inverseless) Haar Random Oracle Model
(with John Bostanci, Aditya Gulati, Yao-Ting Lin)
EUROCRYPT 2025
57. Simultaneous Haar Indistinguishability with Applications to Unclonable Cryptography
(with Fatih Kaleoglu, Henry Yuen)
ITCS 2025
Cryptography in the Common Haar State Model: Feasibility Results and Separations
(with Aditya Gulati, Yao-Ting Lin)
QIP 2025
Copy-Protecting Puncturable Functionalities, Revisited
(with Amit Behera, Zikuan Huang)
TQC 2025
2024
56. Cryptography in the Common Haar State Model: Feasibility Results and Separations
(with Aditya Gulati, Yao-Ting Lin)
TCC 2024
(preliminary version will appear in QCRYPT 2024)
55. Quantum Key-Revocable Dual-Regev Encryption, Revisited
(with Zihan Hu, Zikuan Huang)
TCC 2024
(with Vipul Goyal, Jiahui Liu, Qipeng Liu)
ASIACRYPT 2024
53. NIZKs with Maliciously Chosen CRS: Subversion Advice-ZK and Accountable Soundness
(with Gilad Asharov, Vipul Goyal, Hadar Kaner, Pratik Soni, Brent Waters)
SCN 2024
52. A Modular Approach to Unclonable Cryptography
(with Amit Behera)
CRYPTO 2024
(with Aditya Gulati, Fatih Kaleoglu, Yao-Ting Lin)
EUROCRYPT 2024
50. Pseudorandom Strings from Pseudorandom Quantum States
(with Yao-Ting Lin, Henry Yuen)
ITCS 2024
49. Provable Robust Watermarking for AI-Generated Text
(with Xuandong Zhao, Lei Li, Yu-Xiang Wang)
ICLR 2024
48. ORTOA: A Family of One Round Trip Protocols For Operation-Type Obliviousness
(with Sujaya Maiyya, Yuval Steinhart, Adrian Davila, Jason Du, Divyakant Agrawal, Amr El Abbadi)
EDBT 2024
2023
47. Revocable Cryptography from Learning with Errors
(with Alexander Poremba, Vinod Vaikuntanathan)
TCC 2023
46. On the (Im)Plausibility of Public-Key Quantum Money from Collision-Resistant Hash Functions
(with Zihan Hu, Henry Yuen)
ASIACRYPT 2023
45. Cloning Games: A General Framework for Unclonable Primitives
(with Fatih Kaleoglu, Qipeng Liu)
CRYPTO 2023
QCRYPT 2023
Pseudorandom Quantum States, Revisited: New Properties, Variants, Constructions, and Cryptographic Applications
(with Aditya Gulati, Luowen Qian and Henry Yuen)
QIP 2023 (short plenary talk)
On the Feasibility of Unclonable Encryption, and More
(with Fatih Kaleoglu, Xingjian Li, Qipeng Liu, Mark Zhandry)
QIP 2023 (contributed talk)
2022
44. Pseudorandom (Function-Like) Quantum State Generators: New Definitions and Applications
(with Aditya Gulati, Luowen Qian and Henry Yuen)
TCC 2022
QCRYPT 2022
43. Collusion-Resistant Functional Encryption for RAMs
(with Kai-Min Chung, Xiong Fan, Luowen Qian)
ASIACRYPT 2022
42. Cryptography from Pseudorandom Quantum States
(with Luowen Qian, Henry Yuen)
CRYPTO 2022
QCRYPT 2022
[Twitter summary by Henry]
41. On the Feasibility of Unclonable Encryption, and More
(with Fatih Kaleoglu, Xingjian Li, Qipeng Liu, Mark Zhandry)
CRYPTO 2022
40. Pre-Constrained Encryption
(with Abhishek Jain, Zhengzhong Jin, Giulio Malavolta)
ITCS 2022
Post-Quantum Zero-Knowledge with Space-Bounded Simulation
(with Alex B. Grilo)
A Note on Copy-Protection from Random Oracles
(with Fatih Kaleoglu)
Quantum Cryptography Workshop 2022
2021
39. Unclonable Encryption, Revisited
(with Fatih Kaleoglu)
TCC 2021
38. On the Concurrent Composition of Quantum Zero-Knowledge
(with Kai-Min Chung, Rolando L. La Placa)
CRYPTO 2021
EUROCRYPT 2021
36. Towards Accountability in CRS Generation
(with Gilad Asharov, Hila Dahari, Vipul Goyal)
EUROCRYPT 2021
35. Unbounded MPC from Learning with Errors
(with Abhishek Jain, Zhengzhong Jin, Giulio Malavolta)
EUROCRYPT 2021
2020
2019
2018
2017
2016
15. Delegating RAM Computations with Adaptive Soundness and Privacy (with Yu-Chi Chen, Kai-Min Chung, Huijia Lin and Wei-Kai Lin)2015
12. Indistinguishability Obfuscation from Compact Functional Encryption
2014
2013
2012
4. Complexity of Grobner Basis Detection and Border Basis Detection (with Ambedkar Dukkipati)2011
2018: PKC, ASIACRYPT
2020: TCC
2022: PKC, CRYPTO, Quantum Cryptography workshop (co-organized with Asiacrypt 2022)
2023: EUROCRYPT, ITC, TCC
2024: STACS, TCC, ASIACRYPT (area chair)
2025: ITCS, EUROCRYPT, ArcticCrypt, TCC, QCRYPT, ACM QSec Workshop (co-located with ACM CCS)
Local chair: ITC 2025
Editorial Board: IACR Communications in Cryptography (2024)
For UCSB visitors: There are many options near UCSB for staying. However, many of these options are quite expensive. There are a couple of (relatively) cheaper options, apart from those you can find on AirBnB:
There are many nice places to see in and around Santa Barbara: botanical garden, Mission Church, Santa Barbara zoo, hikes and, of course, beaches.
For UCSB students:
If you are interested in taking my course but have not yet enrolled: please meet me right after the first lecture. If you can't make it the first lecture, meet me after the second lecture. I'm not good with emails, so this is the best way to reach me.
If you have taken one of my courses and interested in receiving a letter of recommendation from me (for BS/MS or Masters): I typically only write letters for students who have secured an A+ in my course and in some rare cases, A. If you have never interacted with me during/after the lectures, it is unlikely that I'll write a letter for you.
If you are interested in doing research: as an undergraduate student, it can be challenging to pursue research. Before deciding on the research area, it is a good first step to understand the research process to make sure that you are comfortable with it. Here are some useful articles:
If you are an undergraduate student interested in pursuing research with me: you should have taken courses CS 138 and CS 178 before reaching out to me. You should have a strong mathematical background and should be comfortable with mathematical proofs. In some rare cases, I'll make an exception.