Physical unclonable functions (PUFs) have attracted interest in demonstrating authentication and cryptographic processes for Internet of Things (IoT) devices. We demonstrated four-dimensional PUFs (4D PUFs) to realize time-varying chaotic phosphorescent randomness on MoS 2 atomic seeds. By forming hybrid states involving more than one emitter with distinct lifetimes in 4D PUFs, irregular lifetime distribution throughout patterns functions as a time-varying disorder that is impossible to replicate. Moreover, we established a bit extraction process incorporating multiple 64 bit-stream challenges and experimentally obtained physical features of 4D PUFs, producing countless random 896 bit-stream responses. Furthermore, the weak and strong PUF models were conceptualized and demonstrated based on 4D PUFs, exhibiting superior cryptological performances, including randomness, uniqueness, degree of freedom, and independent bit ratio. Finally, the data encryption and decryption in pictures were performed by a single 4D PUF. Therefore, 4D PUFs could enhance the counterfeiting deterrent of existing optical PUFs and be used as an anticounterfeiting security strategy for advanced authentication and cryptographic processes of IoT devices.
Physical unclonable functions (PUFs) have attracted interest in demonstrating authentication and cryptographic processes for Internet of Things (IoT) devices. We demonstrated four-dimensional PUFs (4D PUFs) to realize time-varying chaotic phosphorescent randomness on MoS 2 atomic seeds. By forming hybrid states involving more than one emitter with distinct lifetimes in 4D PUFs, irregular lifetime distribution throughout patterns functions as a time-varying disorder that is impossible to replicate. Moreover, we established a bit extraction process incorporating multiple 64 bit-stream challenges and experimentally obtained physical features of 4D PUFs, producing countless random 896 bit-stream responses. Furthermore, the weak and strong PUF models were conceptualized and demonstrated based on 4D PUFs, exhibiting superior cryptological performances, including randomness, uniqueness, degree of freedom, and independent bit ratio. Finally, the data encryption and decryption in pictures were performed by a single 4D PUF. Therefore, 4D PUFs could enhance the counterfeiting deterrent of existing optical PUFs and be used as an anticounterfeiting security strategy for advanced authentication and cryptographic processes of IoT devices.
The rapid expansion of the Internet of Things (IoT) has significantly raised concerns over secure identification and authentication of IoT devices. While physical unclonable function (PUF)-based anticounterfeiting cryptography shows promise, implementing multi-factor authentication (MFA) system with resource-constrained PUF device remains a significant challenge. Here, we demonstrate a multidimensional-encoded optical PUF fabricated with multi-color quantum dots (mQDs), resilient to machine learning attacks, for use in anticounterfeiting MFA. Randomly distributed mQDs in a periodic nanostructure fabricated via nanoimprint lithography generate spatially chaotic, unpredictable multiple security keys when ultraviolet (UV) light is only illuminated. Photoluminescence measurements revealed irregular mQD emission, where disordered distribution-induced Förster resonant energy transfer produces unpredictable color patterns. Our PUF-induced multiple keys were validated through advanced PUF metrics like uniformity, uniqueness, correlation factor, entropy, and even resilience to machine learning attack. We further demonstrate efficient implementation of a cryptography protocol with MFA system for IoT applications using mQDs-based optical PUFs. Material systems with physical unclonable functions (PUF) are needed for secure authentication. Here, a multidimensional-encoded optical PUF fabricated with multi-color quantum dots is demonstrated, for multi-factor authentication.
Abstract A physical unclonable function (PUF) device leverages manufacturing randomness to generate a unique fingerprint for secure authentication, encryption, and counterfeit prevention. Optical PUFs (OPUFs) have gained prominence due to their strong security, light‐based challenge‐response mechanisms, and potential for quantum‐secure encryption. These devices have promising applications for hardware security, authentication, cryptographic key generation, and anti‐counterfeiting measures across multiple industries. This review enlightens the diverse material platforms used for OPUFs, ranging from fiber optics and liquid crystals to advanced semiconductor nanocrystals and plasmonic metasurfaces, each offering distinct optical characteristics that impact security strength. While no single material system dominates the field, hybrid and multi‐model approaches integrating low‐dimensional materials are being explored to enhance reliability and scalability. Finally, the challenges and future perspectives are outlined, including adaptive OPUFs architectures, utilizing artificial intelligence (AI) for challenge‐response generation, and their integration into quantum communication networks, highlighting how next‐generation semiconductor materials can further advance OPUFs technologies.
With the rapid expansion of digital communication and the Internet of Things (IoT), hardware-level security and anti-counterfeiting technologies have become increasingly important. Traditional cryptographic systems depend on mathematically generated keys, which are vulnerable to duplication and physical attacks. In contrast, Physical Unclonable Functions (PUFs) utilize inherent physical randomness to produce unique, unpredictable responses, offering a hardware root of trust for secure authentication. Among various PUF implementations, optical PUFs (O-PUFs) have attracted attention due to their high entropy density, non-contact readout, and immunity to electromagnetic interference. These systems exploit light–matter interactions, such as scattering, reflection, and emission to generate random optical fingerprints. In recent years, photoluminescent (PL) materials have emerged as promising candidates for constructing material-based optical PUFs. Their intrinsic emission randomness, strong optical signals, and tunable luminescence enable secure encoding without complex nanofabrication. Materials such as perovskite quantum dots and lanthanide-based metal–organic frameworks (MOFs) combine high photoluminescence efficiency, environmental stability, and low-cost processability, making them ideal for scalable optical authentication applications. This thesis explores the development and performance evaluation of photoluminescent based PUFs for optical security and anti-counterfeiting. Three types of luminescent materials, namely perovskite quantum dots, lanthanide-based MOFs, and intermolecular charge-transfer (CT) complexes are qualitatively analyzed as potential optical PUF platforms. A particular focus is placed on the statistical evaluation of Terbium-based MOFs (Tb-MOFs) and CT complexes. For Tb-MOFs, two entropy sources are examined: the spatial distribution of MOF microstructures and the randomness in PL intensity. Similarly, CT complexes are evaluated based on their disordered geometric topology. Standardized image processing, including optical imaging, grayscale conversion, and binarization, is employed to extract PUF features. Quantitative metrics such as uniqueness, reliability, and encoding capacity are analyzed. The results demonstrate that both Tb-MOF and CT-based systems achieve high encoding capacity and stable reproducibility within a sub-millimeter scale. This study validates the feasibility of luminescent materials as robust optical PUFs and provides a foundation for scalable, photostable, and intelligent optical authentication systems
The Internet of Things (IoT) has ushered in significant advancements in networked technologies, yet it simultaneously raises concerns about the security and privacy of connected devices. Traditional authentication methods based on cryptographic protocols are increasingly vulnerable to attacks as the number of devices grows and attackers develop more sophisticated strategies. In this paper, we propose a novel quantum-based authentication method using Quantum Physical Unclonable Functions (QPUFs) to address the security challenges in IoT devices. Quantum PUFs exploit the inherent quantum properties of devices to generate unique, unclonable responses to challenges, providing a high level of security and resilience against attacks such as cloning, spoofing, and interception. We present the architecture of the proposed quantum authentication system, discuss the challenge-response protocol, and evaluate the system’s performance. Experimental results show that this approach offers strong security guarantees with minimal computational overhead. We Evaluate the Security, Scalability of our approach in simulated adverse IoT environment.
Abstract Physically Unclonable Functions (PUFs) offer a promising solution for Internet of Things (IoT) security, yet most optical PUFs are limited to rigid binary authentication. To address this, a novel optical PUF based on chaotic polarization patterns from self‐assembled Diethyl 2,5‐dihydroxoterephthalate (DDT) crystals grown on flexible, large‐area MoS 2 films is introduced. By harnessing the unique polarized photoluminescence (PL) from the random crystal domains, a tri‐modal authentication scheme is demonstrated that provides enhanced security resolution. From the polarized PL images, a 1024‐bit key is extracted and analyzed. The system yields three statistically distinct and clearly separable Hamming distance distributions: intra‐HD (0.0157 ± 0.0061), mutual‐HD (0.2540 ± 0.0229), and inter‐HD (0.4986 ± 0.0149). This tri‐modal verification goes beyond a simple accept/reject decision, offering a more nuanced and robust authentication framework. The PUF exhibits excellent randomness, passing NIST statistical test. The practicality of this approach is further showcased through a proof‐of‐concept smartphone application. This work establishes a new paradigm for flexible, high‐security optical PUFs, holding significant promise for next‐generation IoT and authentication applications.
Integrated circuit anti-counterfeiting based on optical physical unclonable functions (PUFs) plays a crucial role in guaranteeing secure identification and authentication for Internet of Things (IoT) devices. While considerable efforts have been devoted to exploring optical PUFs, two critical challenges remain: incompatibility with the complementary metal-oxide-semiconductor (CMOS) technology and limited information entropy. Here, we demonstrate all-silicon multidimensionally-encoded optical PUFs fabricated by integrating silicon (Si) metasurface and erbium-doped Si quantum dots (Er-Si QDs) with a CMOS-compatible procedure. Five in-situ optical responses have been manifested within a single pixel, rendering an ultrahigh information entropy of 2.32 bits/pixel. The position-dependent optical responses originate from the position-dependent radiation field and Purcell effect. Our evaluation highlights their potential in IoT security through advanced metrics like bit uniformity, similarity, intra- and inter-Hamming distance, false-acceptance and rejection rates, and encoding capacity. We finally demonstrate the implementation of efficient lightweight mutual authentication protocols for IoT applications by using the all-Si multidimensionally-encoded optical PUFs.