design of chipless structures, and more generally the research for efficient performance, remains a hot topic subject with very rapid development [4; 5; 6; 7; 8]. The best performances published in the last two years reach about 30 bits but remains for the majority around 20 bits, corresponding to spatial density in the range of 1 bit/cm\({}^{2}\), very exceptionally around 10 bits/cm\({}^{2}\) or higher. In contrast, the Terahertz Identification (THID) development is in its early stages and is currently limited by the development of the THz technologies, not only in terms of cost and compactness, but also in terms of the speed-reliability compromise of the reader, which is crucial for the intended applications. THID approaches have been initiated in 2003 by [PERSON] [9] who designed a THz hologram embedded in a dielectric material, which was opaque in the visible range but transparent in the THz one. In 2011, we proposed to encode binary information in the spectral response transmitted or reflected by tags, based on 1D quasi-periodic multilayer structures [10; 11]. The information is thus contained in the volume of the tag, which can be directly embedded in the product to identify or its package. Thereby, the stealth of the tag does not make the latter visible at first glance. In real-word scenarios, its position should be either located by a specific design at the surface, or even kept secret as an additional level of protection, with a reading that would not be visible to everyone. This device principle was taken up in 2013 to encode binary information in the time domain by using the echoes of the incident wave reflected at the interfaces of the tag [12]. More recently, THID has attracted more pronounced attention due to advances in THz technologies, coupled to the evident possibilities to develop breakthrough solutions in order to push the limits of currently used technologies. In 2015, [PERSON] et al. [13] demonstrated an adaptation of the barcode for the THz range, using successive layers of polyethylene. In 2018, a 2D photonic-crystal slab matrix made of silicon was proposed as large-capacity tag, using both frequency and spatial domains [14]. Even if an interesting capacity of 48 bits/cm\({}^{2}\) has been demonstrated, the device made of a periodic array of holes in a silicon slab remains unachievable by current low-cost industrial manufacturing techniques. In 2019, [PERSON] et al. [15] proposed a theoretical THID tag structure based on square graphene loops deposited on dielectric Topas material. A 2-bits Graphene Terahertz Identification Tag (GTIDT), with geometrical dimensions of several micrometers was first showed. Moreover, multilayer GTIDTs were investigated to form 3-bits structures. In 2019, we also demonstrated the principle to use a multilayer device including random inclusions in order to be used for THID identification, by using THz imaging associated with the Shift Invariant Wavelet Packet Decomposition (SIWPD) analysis method [16]. Finally, we also proposed a novel structure of device dedicating to identification and authentication, based on a diffractive grating engraved on a low-cost substrate [17]. By using different statistical analyses (Principal Component Analysis-PCA and Linear Discriminant Analysis-LDA), we show that the frequency signature of such a tag can be authenticated with a success rate of 99.994%. More recently, in 2020, [PERSON] et al. proposed a solution for real-time identification by combining a multi-wavelength injection-seeded THz parametric oscillator and a convolutional neural network algorithm [18]. A 46 bits' tag has been demonstrated by combining 3 different materials in etalon type cavities of different thicknesses and arranged in a 2D array. At the same time, [PERSON] et al. proposed a patch antenna array (2 \(\times\) 2), built in a CMOS, to be used for identification at 260 GHz [19].