Si_6−z Al _z O _z N_8−z (β-SiAlON):Eu²⁺ is known as a high brightness green phosphor. When β-SiAlON:Eu²⁺ is excited with UV light (approximately 265 nm), a curved decay afterglow is observed as a result of the trap levels created by the defects in the host crystal. However, the defect signals are hardly detected by electron spin resonance (ESR) and thermoluminescence (TL), which are common defect detection methods. Non-doped (Eu = 0) β-SiAlON emits blue light from a nitrogen defect, and the defect can be detected by time-resolved fluorescence (TR-F) measurement at 15 K. Similarly, upon measuring TR-F at 15 K for Eu-doped β-SiAlON, a blue emission (460 nm) is detected in addition to the green emission of Eu²⁺ (530 nm). The green emission has an afterglow of several milliseconds that decays with the same decay curve as the blue emission of the defect, and its time constant is 5–6 ms. This blue emission is quenched by the Eu concentration and temperature. The Si dangling bond signal intensity, observed by ESR, and the glow intensity, observed by TL, also decrease with the increment of the Eu concentration. It is difficult to detect the defect as an electron trap owing to the interaction between Eu²⁺ and the nitrogen defect. However, the afterglow arising from the electrons trapped at the defect level does not decrease with the Eu concentration. The blue emission was quenched at room temperature but the afterglow was not reduced, which also affected the light emission above room temperature. Therefore, it is possible to detect nitrogen defects optically by TR-F at low temperature, as well as the Eu²⁺ afterglow of several milliseconds.

Si _{6- z} Al _z O _z N ₈ - _z（β-SiAlON）：Eu ²⁺被称为高亮度绿色荧光粉。当β-SiAlON：Eu ²⁺ 当被紫外光（约265nm）激发时，由于主体晶体中的缺陷产生的陷阱能级而观察到弯曲的衰减余辉。然而，通过常见的缺陷检测方法电子自旋共振（ESR）和热致发光（TL）几乎无法检测到缺陷信号。未掺杂（Eu = 0）的β-SiAlON会因氮缺陷发出蓝光，可以通过在15 K下进行时间分辨荧光（TR-F）测量来检测该缺陷。类似地，在15 K下测量TR-F对于Eu掺杂的β-SiAlON，除了Eu ²⁺的绿色发射之外，还检测到蓝色发射（460 nm）（530 nm）。绿色发射的余辉为几毫秒，其衰减与缺陷蓝色发射的衰减曲线相同，并且其时间常数为5–6 ms。Eu浓度和温度可猝灭这种蓝色发射。通过ESR观察到的Si悬空键信号强度以及通过TL观察到的辉光强度也随着Eu浓度的增加而降低。由于Eu ²⁺之间的相互作用，很难将缺陷检测为电子陷阱和氮缺陷。但是，由缺陷水平处俘获的电子引起的余辉不会随着Eu浓度而降低。蓝色发射在室温下淬灭，但余辉没有减少，这也影响了室温以上的发光。因此，可以通过TR-F在低温下光学检测氮缺陷，以及几毫秒的Eu ²⁺余辉。