InAs/InP

Sample 10

Cathodoluminescence (CL) measurement

Rhodamine B in Ethanol Solution

(2

Sample 9

Measurement of Raman spectroscopy

10K

Condition

Electron

Probe

Accelerating Voltage

Current

5 kV

10 nA

The data on the right show images of

cathodoluminescence (CL) emitted from

InAs islands in an InAs/InP multiple

quantum well structure, observed with a

scanning electron microscope (SEM) to

which a light collection system and a

monochromator were installed. The right-

hand CL images were taken with the

SEM using a Ge PIN photodiode. These

images are not clear due to external

noise such as cosmic rays. In contrast,

the left-hand data taken with an R5509-

42 photomultiplier tube shows clear,

sharp CL images with a high S/N ratio.

The R5509-42 allows high-sensitivity CL

measurements in the near infrared re-

gion, which are expected to prove useful

in optical evaluations of samples, analy-

sis of inorganic or organic substances,

and other near infrared spectroscopy.

Cathodoluminescence (CL) Measurement

When a sample is irradiated by high-veloc-

ity electron beams, electron-hole pairs in

the sample are excited and then recom-

bine while producing a characteristic lumi-

nescence known as cathodoluminescence

(CL). Information on the internal electron

structures of the sample can be studied by

measuring this luminescence.

SAMPLE TEMPERATURE

Raman spectroscopy is effective in

studying the structure of molecules in a

solution. In particular, near infrared Ra-

man spectroscopy enables measure-

ment of samples which were previously

impossible with conventional methods

using visible light excitation because of

the influence of fluorescence. In this ap-

plication, clear Raman spectra of solute

rhodamine B (marked by

M) are meas-

ured, as well as a Raman spectrum of

ethanol solution. This data was obtained

with weak excitation light averaging 10

mW output using pulsed excitation light

and gate detection method under fluor-

escent room lighting conditions.

TPMHB0452EB

1600

1200

1400

1000

800

RHODAMINE B POWDER

ETHANOL

SAMPLE

EXCITATION LIGHT: LD-PUMPED

ND: YAG (1064 nm)

10 mW, 10 ns pulse, 10 kHz

SAMPLE TEMPERATURE: 77 K

(

)

room

temperature

990nm

990nm

1010nm

1020nm

1030nm

1040nm

R5509-42

Ge PIN-PD

77K

Photos: By courtesy of Prof. Y. Takeda, Dept. of Materials Science and Engineering, Graduate

School of Engineering, Nagoya University;

Prof. A. Nakamura, Center for Integrated Research in Science and Engineering, Nagoya

University

300K

SAMPLE TEMPERATURE