2D Van der Waals Rare Earth Material Based Ratiometric Luminescence Thermography Integrated on Micro–Nano Devices Vertically

Abstract

Up to now, there are many methods for temperature sensing such as thermo couples, thermistor, thermovision, and ultrasound techniques. These thermom eters generally detect temperature on a macro scale which cannot satisfy the remote and realtime thermography inte grated on micro-nano devices. [8,9] Lumi nescence thermography can achieve high spatial resolution and remote operation because of the lower diffraction limit and high transparency. [4,10,11] The most reported luminescence thermography are based on semiconductor films with tem peraturedependent luminescence such as perovskites. [4,12,13] However, these lumines cent semiconductor films cannot achieve vertical integration and will incur interfer ence on the performance of chips due to the semiconductor nature.2D insulated van der Waals (vdW) rare earth (RE) materials have both the layered structure and intriguing temperature dependent luminescence properties. [14,15] 2D vdW RE materials have no dangling bonds and large spe cific surface area, which can be beneficial for achieving a better thermal contact with the target and high sensitivity. [16,17] With layered structure and insulated properties, 2D vdW RE mate rials can be easily integrated on semiconductor chips vertically without dangling bonds, so that a highdensity integration can be realized. [18,19] Besides, 2D vdW RE materials have excellent luminescence properties especially for the extremely narrow and multiple emissions spanning ultraviolet, visible, and infrared regions, which are ideal for probing temperature. [20,21] Luminescent thermometers can be achieved by monitoring the single emission, luminescence lifetime, and polarization. [4,22] However, single emissionbased luminescent thermometers will be badly affected by local fluctuation such as the concentra tion, size, and geometry of luminescent materials. [23,24] Lumi nescent thermometers based on lifetime and polarization need more complex and expensive employment, which are also not convenient for data processing. [25] Therefore, luminescence thermometers are better to detect intensity of two discrimi nable emission peaks to achieve ratiometric sensors. [26,27] Ratio metric luminescence thermometry can avoid optoelectronic fluctuations from the excited laser sources and detectors due Remote and real-time thermography integrated on micro-nano devices vertically can promote the integration while estimating their operation, which is hitherto challenging. Here, the ratiometric luminescence thermography integrated on micro-nano devices vertically based on 2D van der Waals (vdW) rare earth (RE) material ErOCl is demonstrated. Ratiometric luminescence intensity varies linearly with temperature deriving from the thermal activation between two thermally coupled levels. Typically, this ratiometric micro-nano thermometer has a wide sensing range (300-700 K), high relative sensitivity (2.2% K −1 at 300 K), and high repeatability. With layered structure and insulated properties, 2D ErOCl can be easily integrated on the target chips vertically without...

van der Waals Heterostructures Based on Nanolayered Paramagnetic Tm(II) Compounds and Boron Nitride for Investigating Spin Frustration

“…This has some precedent for these known vdW materials 9 and would be beneficial to extend to new systems such as those that contain rare-earth metal ions. Rare-earth metal-containing thin films synthesized via other methods are garnering interest as molecular sensors, 21 luminescent materials, 22 and spin liquid candidates. 23 Recently, an organometallic rare-earth compound, [(THF)-Cs(μ-η 5 :η 5 -Cp′) 3 Yb II ] n (1; Cp′ = C 5 H 4 SiMe 3 ), was synthesized and found to have a layered structure (see Figure 1) that could potentially be exfoliated to form thin films.…”

“…This has some precedent for these known vdW materials and would be beneficial to extend to new systems such as those that contain rare-earth metal ions. Rare-earth metal-containing thin films synthesized via other methods are garnering interest as molecular sensors, luminescent materials, and spin liquid candidates …”

Electric‐Tunable Photoluminescence of 2D ErOCl for High‐Security Encryption of Programmable Information

“…X-ray diffraction (XRD) of ErOCl crystals in Figure S1b, Supporting Information, shows obvious peaks at (003), (006), (009), and (0012), [31] which verifies that ErOCl crystals belong to the hexagonal space group (R-3m) with vdW layered structure. [32,33] Therefore, the High-security encryption has always been important in economic and military fields as well as in daily life. 2D van der Waals (vdW) rare-earth (RE) materials have advantages in photoluminescence (PL) modulation to achieve high-security encryption because of their multiple sharp emission peaks, which will facilitate the multimode regulation for high-security encryption of programmable information.…”

“…The relationship between I 525 / 545 and temperature is I 525/545 = 0.002T-0.518, which can be used for temperature monitoring. [33] The mechanism of the opposite trend induced by temperature change for the above two transitions is depicted in Figure 2a. [26] 2 H 11/2 and 4 S 3/2 are two thermal coupling energy levels.…”

“…The thermal stability of ErOCl flakes is good and has been measured in our previous work. [33] We also measured the repeatability and stability of this encryption device shown in Figure S11, Supporting Information. It is clear that the encryption device keeps switching under the modulation of electricity on the 1st day, 3rd day, and 4th day, which indicates the encryption device has good repeatability and stability.…”