We have developed a femtosecond single-shot spectroscopic technique to measure irreversible changes in condensed phase materials in real time. Crossed echelons generate a two-dimensional array of time-delayed pulses with one femtosecond probe pulse. This yields 9 ps of time-resolved data from a single laser shot, filling a gap in currently employed measurement methods. We can now monitor ultrafast irreversible dynamics in solid-state materials or other samples that cannot be flowed or replenished between laser shots, circumventing limitations of conventional pump-probe methods due to sample damage or product buildup. Despite the absence of signal-averaging in the single-shot measurement, an acceptable signal-to-noise level has been achieved via background and reference calibration procedures. Pump-induced changes in relative reflectivity as small as 0.2%−0.5% are demonstrated in semimetals, with both electronic and coherent phonon dynamics revealed by the data. The optical arrangement and the space-to-time conversion and calibration procedures necessary to achieve this level of operation are described. Sources of noise and approaches for dealing with them are discussed.

1.
M. M.
Martin
and
J. T.
Hynes
,
Femtochemistry and Femtobiology: Ultrafast Events in Molecular Science
(
Elsevier
,
Amsterdam
,
2004
).
2.
C.
Rulliere
,
Femtosecond Laser Pulses: Principles and Experiments
(
Springer
,
New York
,
2005
).
3.
L.
Dhar
,
J. T.
Fourkas
, and
K. A.
Nelson
,
Opt. Lett.
19
,
643
(
1994
).
4.
J. T.
Fourkas
,
L.
Dhar
,
K. A.
Nelson
, and
R.
Trebino
,
J. Opt. Soc. Am. B
12
,
155
(
1995
).
5.
R.
Weinkauf
,
L.
Lehr
,
D.
Georgiev
, and
E. W.
Schlag
,
Appl. Phys. B: Lasers Opt.
64
,
515
(
1997
).
6.
Y.
Makishima
,
N.
Furukawa
,
A.
Ishida
, and
J.
Takeda
,
Jpn. J. Appl. Phys.
45
,
5986
(
2006
).
7.
T.
Lang
and
M.
Motzkus
,
J. Opt. Soc. Am. B
19
,
340
(
2002
).
8.
M. R.
Topp
,
P. M.
Rentzepis
, and
R. P.
Jones
,
Chem. Phys. Lett.
9
,
1
(
1971
).
9.
A. R.
Cook
and
Y.
Shen
,
Rev. Sci. Instrum.
80
,
073106
(
2009
).
10.
G. P.
Wakeham
and
K. A.
Nelson
,
Opt. Lett.
25
,
505
(
2000
).
11.
K. Y.
Kim
,
B.
Yellampalle
,
A. J.
Taylor
,
G.
Rodriguez
, and
J. H.
Glownia
,
Opt. Lett.
32
,
1968
(
2007
).
12.
G. P.
Wakeham
,
D. D.
Chung
, and
K. A.
Nelson
,
Thermochim. Acta
384
,
7
(
2002
).
13.
P. R.
Poulin
and
K. A.
Nelson
,
Science
313
,
1756
(
2006
).
14.
H.
Zeiger
,
J.
Vidal
,
T.
Cheng
,
E.
Ippen
,
G.
Dresselhaus
, and
M.
Dresselhaus
,
Phys. Rev. B
45
,
768
(
1992
).
15.
B.
Saleh
and
M.
Teich
,
Fundamentals of Photonics
(
Wiley & Sons
,
Hoboken, NJ
,
2007
), p.
964
.
16.
See supplementary material at http://dx.doi.org/10.1063/1.4893641 for a summary and comparison to other available single-shot methods, probe beam array cross-talk and additional noise sources in single-shot measurement, and modeling the probe beam array at the sample plane.

Supplementary Material

You do not currently have access to this content.