A Cr³⁺ luminescence based ratiometric optical laser power meter

Abstract

Chromium doped luminescent phosphors display numerous spectral features that can be useful for designing modern multi-functional materials.

Upconverting nanoparticles as primary thermometers and power sensors

“…yielding a maximum value of 0.5% W −1 •cm 2 at 29.0 W cm −2 (Figure 5D), which is higher than the value reported for the luminescent Cr 3+− based ratiometric radiation sensor, 0.07% W −1 cm 2 , (Marciniak et al, 2022).…”

“…This complicates accurate temperature readout but provides an opportunity to explore NIR P D optical readout, as demonstrated herein. To the best of our knowledge, only one luminescent excitation density ratiometric sensor for the visible spectral range was reported by (Marciniak et al (2022)). There, the intensity ratio of 4 T 2(g) → 4 A 2(g) and 2 E (g) → 4 A 2(g) transitions of GdAl 3 (BO 3 ) 4 :Cr 3+ nanoparticles was used to measure the excitation power density at 445 nm and 532 nm.…”

“…The designed material reached temperatures as high as 143 °C, even at low excitation power density. According to the excitation power density, the heat generated in the system leads to the thermalization of the 4 T 2(g) state inducing a change in the intensity ratio (Marciniak et al, 2022), and thus, the working principle of this Cr 3+ ratiometric laser power meter is, in fact, temperature related.…”

Metal–Organic Framework Optical Thermometer Based on Cr3+ Ion Luminescence

“…The luminescence properties of transition metal ions, such as Cr 3+ , originate from d–d electronic transitions, which are not shielded by the outer orbitals, unlike the 4f orbitals in trivalent lanthanide ions . Consequently, the spectroscopic characteristics of Cr 3+ ions are strongly affected by the crystal field strength of the matrix material; thus, the emission type, range, and thermal quenching rate can be tuned by changing the matrix type. − The sensitivity of spectroscopic properties to the change of crystal field parameters plays a particular role in research on TM-based luminescence thermometers. ,, The irradiation with 405 nm wavelength excites a higher 4 T 1g level. The nonradiative energy transfer causes the increase in the population of the lowest vibrational level of 2 E g .…”

Spectral Broadening in Cr3+-Doped Sr0.92Mg0.91Al10.1O17 NIR Phosphor Realized by Multi-crystallographic Site Occupation

“…Near-infrared light (700–1400 nm) is an electromagnetic wave that exists between visible and mid-infrared light and is greatly utilized in plant growth, night vision, medical imaging, food analysis, and so on. − In recent years, NIR pc-LED, which is recognized as a new generation of NIR light source, has garnered a lot of attention due to its high efficiency and compact size. − Cr 3+ is one of the most frequent activators of NIR phosphors. Its luminescence is greatly impacted by the crystal field with a narrow emission in a strong crystal field and a broadband one in a weak crystal field.…”