  Information security is of great importance for modern society with all
things connected. Physical unclonable function (PUF) as a promising hardware
primitive has been intensively studied for information security. However, the
widely investigated silicon PUF with low entropy is vulnerable to various
attacks. Herein, we introduce a concept of bionic optical PUFs inspired from
unique biological architectures, and fabricate four types of bionic PUFs by
molding the surface micro-nano structures of natural plant tissues with a
simple, low-cost, green and environmentally friendly manufacturing process. The
laser speckle responses of all bionic PUFs are statistically demonstrated to be
random, unique, unpredictable and robust enough for cryptographic applications,
indicating the broad applicability of bionic PUFs. On this ground, the
feasibility of implementing bionic PUFs as cryptographic primitives in entity
authentication and encrypted communication is experimentally validated, which
shows its promising potential in the application of future information
security.
